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DPChallenge Forums >> Out and About >> DPC Mentorship - Macro
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Showing posts 1 - 25 of 81, descending (reverse)
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01/09/2006 02:12:54 PM · #1
I'm using it together with the 50-200, that is I hold the 50mm in front of it. When I do so, I don't notice a change either way I hold the 50mm.
Macro mode? I used manual, and anyway, the 50mm is not connected to the camera when reversed.
Maybe you could point me out to the reverse tutorial?
01/09/2006 11:08:13 AM · #2
Sorry for the delay I was without net for a few months. You can shoot macro with the 50mm lens as is if your cam has a macro mode.. Most likely it does. By reversing the lens you will get a lot more magnification (not sure why you didn't). There is a tutorial on how to reverse the lens here on DPC. I am not sure what the exact magnifications are if the lense is reversed but I would guess from some of my stuff it would heve to be over 100X. If I have some time this week i will check into this some more and see if I can't get you some more definate answers.
12/31/2005 08:23:07 AM · #3
...
12/18/2005 01:49:36 PM · #4
Bump.
12/16/2005 03:58:48 PM · #5
I got me a 50mm 1.8 II today (W00t!) and the results are great. Of course I also had to try it together with my zoom lens for macro. Muuuuch better than reversing the kit lens.
However, why does the 50mm need to be reversed? I tried it the other way round, and didn't notice any difference! I'd like to post shots for the different methods, but I can't tell which one is which anymore...
Is it about contacts and rings or is there a difference in optics?
11/26/2005 06:28:02 PM · #6
Originally posted by gloda:

I talked to a salesman about possibilities for macro photography, and he told me about a technique which I have never heard of and which sounds rather weird. He suggested to paint a roll of toilet paper (the tube in the middle) all black and to put it in between the camera and the lens. This then ought to work like an extension tube (w/o contacts, of course), reducing the minimal focusing distance.
Has anyone ever heard of this technique and made any experiences with it?


We actually did that back in 1972 or so, with film Nikon. Magnification was certainly there, but alignemnet was a bitch and results were mixed :-)

R.
11/26/2005 05:54:21 PM · #7
I talked to a salesman about possibilities for macro photography, and he told me about a technique which I have never heard of and which sounds rather weird. He suggested to paint a roll of toilet paper (the tube in the middle) all black and to put it in between the camera and the lens. This then ought to work like an extension tube (w/o contacts, of course), reducing the minimal focusing distance.
Has anyone ever heard of this technique and made any experiences with it?
09/15/2005 09:12:43 AM · #8
Well it looks like this is the conclusion of the Macro mentorship program. I hope that atleast some of you learned somthing new and that all of you enjoyed the little program. I had inteded on the mentorship being a reoccuring thing but unfortunatley I will have to let my membership expire. I apreciate all ofthe feedback and participation from all of you who joined. Thank you and have a wonderfull time shooting those macros!!

Tristalsk
09/09/2005 08:51:18 AM · #9
I can't think of any reason they wouldn't work. You may even be able to get a thread adaptor for them to get them to work on your 52mm. My speculation is you would get a bit a black ring around the edges of and possibly a little light loss (in comparison to the 50mm). I have used simular lenses and the results were not to bad.
09/08/2005 01:46:39 PM · #10
I guess that makes sense. The kit lens is quite heavy for reversing already. I still have to experiment what effect different focal lenthes (is that a real plural?) have, since I work with two zoom lenses.

My father has found 4 old close-up lenses from his analog Olympus, but they're 49mm, too small. Do you think they would have worked if they had the right size (52mm)?
09/08/2005 09:03:37 AM · #11
I have used a reversing ring on lenses up to 100mm. However remember Magnification= Extension/ focal length. With a 50mm lens and 50mm of extension you are at life size. To get the same magnification with a 100mm lens you need 100mm of extension. So the only real reason I can come up with for primarily using the 50mm prime is that it is small and compact. Reversing a 100 is large, heavy, and unwieldly. The results are not much better if any. I also tend to loose a little light and get a bit of difraction with the other lenses. So to put it simply you can use the others but the 50mm justs seems to hit the sweet spot.

Message edited by author 2005-09-08 09:06:46.
09/08/2005 04:23:36 AM · #12
Thanks for the "mumbo-jumbo", I think that will come in handy if ever I find a way to shoot moving subjects.

One thing I keep wondering about: Why do people always reverse 50mm lenses? Is there a special characteristica that makes them work better for this technique than other lenses? Does it have somehting to do with the fact that it is such a common prime lens?
09/07/2005 10:24:58 AM · #13
Uh mathematics. Ii will take me some time to get through this :)
09/07/2005 09:23:54 AM · #14
My apologies for the long delay before this lesson. I am in the process of moving. As you can imagine that has realy managed to put a strain on my time. But Alas it it finaly here. The 4th and final "schedualed or planed" lesson. So grab a HUGE!!! mug of coffee and try to enjoy.

Lesson 4 Technical Mumbo Jumbo and The Digital Darkroom.

The more the magnification, the less DOF you get. There is no getting around that. I try to use what little I get as best I can. Furthermore, I try to take the image such that it will not need much “developing” in the digital darkroom. In reality, I find that such perfect images are few and far between.

When working in the digital darkroom, my goal is typically not to alter the image, but rather to improve upon what the camera gave me. Occasionally though, I will alter the image by adding clouds to the sky, cloning away unwanted items, or in rare cases, replacing the background.

I have also worked on a technique of using more than one image (taken within seconds) that have different planes of focus and compositing them for increased DOF (I am most likely to do this with extreme macros because DOF is so limited there). The milkweed beetle shown earlier is an example.

Here are some digital darkroom tips:

1. Take a lot of shots, trying to vary the plane of focus a bit on each so that you are likely to get a couple that hit the sweet spot so to speak.

2. Get used to deleting most of the shots you take. As you gain skill, the hit rate goes up a bit (sometimes).

3. Rotating, cropping, adjusting the levels curves, saturation, and contrast, as well as sharpening the subject and blurring the background are the basics of developing the image.

4. Masking is hiding areas of the image, so that you can work on other areas without affecting the hidden areas. Typically one might mask the foreground so that the background (BG) can be worked on. I typically do this so that I can give the BG a bit of a blur to remove digital noise (since I don't have one of the high end digital SLR's that give relatively noiseless backgrounds). Creating a mask can be tedious and can be done lots of different ways. I like the "magic wand" tool that selects similar areas on the basis of color. I typically use that first and then refine the mask with other tools.

5. Another tool I have found find useful in the digital darkroom is a graphics tablet, which allows me to use a pen instead of a mouse to control the cursor. I am currently in the market for a new one. My old one died about a year back.

Calculating Exposure Compensations

The basic idea is that, once you have figured out your image magnification (more about that later), the exposure factor E can be computed as follows:

M = magnification
E = (M + 1)(M + 1) = (M + 1)square

The table gives some examples. The first column gives the magnification M, and the second column gives the corresponding exposure factor. By multiplying a given shutter time with the exposure factor, you obtain the shutter time you have to use in order to compensate for the loss of light. The third column gives an example. If normally (in the given light situation) you would use 1/1000 as shutter time, with a M of 0.4 you have to double the exposure time to 1/500.
M (M+1)² 1/1000 : (M+1) f/8 : stops
0.1 1.21 826 1.10 8.8 0.3
0.2 1.44 694 1.20 9.6 0.5
0.3 1.69 592 1.30 10.4 0.8
0.4 1.96 510 1.40 11.2 1.0
0.5 2.25 444 1.50 12.0 1.2
0.6 2.56 391 1.60 12.8 1.4
0.7 2.89 346 1.70 13.6 1.5
0.8 3.24 309 1.80 14.4 1.7
0.9 3.61 277 1.90 15.2 1.9
1 4.00 250 2.00 16.0 2.0
1.1 4.41 227 2.10 16.8 2.1
1.2 4.84 207 2.20 17.6 2.3
1.3 5.29 189 2.30 18.4 2.4
1.4 5.76 174 2.40 19.2 2.5
1.5 6.25 160 2.50 20.0 2.6
1.6 6.76 148 2.60 20.8 2.8
1.7 7.29 137 2.70 21.6 2.9
1.8 7.84 128 2.80 22.4 3.0
1.9 8.41 119 2.90 23.2 3.1
2 9.00 111 3.00 24.0 3.2

or for somthing a bit more ledgable

This is all very useful when you are working with available light, but it becomes somewhat cumbersome when you want to use a flash, and you don't have a TTL-flash mode on your camera, or for one reason or another don't want to use the TTL-flash.

When using flash light as the primary source of light, shutter time has no role whatso-ever (provided you stay below or at the synchronisation time). With flash light, we are first and foremost interested in apertures, and we have to compensate the light loss by changing the aperture value and/or changing the power/distance of the flash.

Of course, to return to the example, if working with a M=0.4 implies that 1/1000 becomes 1/500, we can deduce that M=0.4 needs a compensation of one stop (either by halving the shutter time, or by opening the aperture one value).

However, this can be done in a more straightforward way. In the fourth column of the table, we calculate (M + 1) instead of (M + 1)(M + 1).

Now, that is convenient. By multiplying the working aperture value (as indicated on our objective), say f/8, with (M+1), we obtain the effective aperture for the given magnification. The fifth column gives some examples for aperture f/8. An aperture of f/8 with a magnification of M=0.4 gives an effective aperture of f/11, basically what we could expect from the previous example.

Yet, the effective aperture values will not always be a practical solution in applied work. Better objectives may allow you to choose the aperture in ½ or even 1/3 of a stop, but even then it would be far more convenient to have the relationship between magnification and exposure compensation directly in stops, instead of having to decide whether a value such as 18.4 is closer to f/16 + 1/3, or is closer to f/16 + 2/3.

Well, this can done. The next graph gives the exposure compensation in stops for magnifications between 0.1 and 10. This is definitely more convenient : at a M equal to 10, the exposure factor is (10+1)(10+1)=121, obliging you to do some mental calculations when you actually only wanted to make pictures. In my opinion, it is much more easy to know you have to compensate for 7 stops in that case. It is also a much more general approach, since it allows you to compensate either by reducing time or by opening the aperture, whatever comes in handy.






In order to use these graphs, it is not necessarily to know how they are obtained, so feel free to skip the next section. However, for those, like me, who don’t accept without (some) understanding, here is how I calculated them (the formulas are also convenient if you want to reproduce the graphs in your own spreadsheet).

When you look at the second column in the table, and concentrate on the bold figures, you will notice that when you loose a stop of light, the exposure factor E goes consecutively from 2 (well, 1.96) to 4, to 8. These are all powers of 2. What you get there is that the power to which you have to raise the number 2 in order to obtain the exposure factor E for a given M, is in fact the number which says how much stops you loose for that given magnification. If this number of stops is denoted as S, and using some (long forgotten ?) highschool maths, we get :

E = 2^S (2 to the power S).

log 2 (E) = S

By converting this to a more common base,

log 2 (E) = log 2 (e)* log e (E)

and some rearrangements, we get

S = (1/ln(2))*ln(E)

which can be readily introduced in most spreadsheet software.

How to determine the magnification M ?
In 35mm photography, the negative will be 24mm times 36mm. So if you are wondering what magnification you are working with, just hold a ruler in the position that is in focus, and count the number of mm on the ruler that are visible on your ground glass. If you only see 18 mm (with the camera and the ruler in the same horizontal position), the implication is that you have a M equal to 36/18, i.e. 2/1.

However, don’t forget that there are only a few cameras that really give you a 100% view on the ground glass. Consult your manual. If you e.g. only get a 82% view, you will have to reduce the 36mm accordingly.

Some notes about the limitations of the above formulas
The formula which states that exposure compensation is equal to (M+1)(M+1) is in fact only valid for symmetric objectives. Loosely speaking, an objective is symmetric if the aperture you see when looking to the front and looking to the back, is approximately equal. This is generally the case for normal focal distances (i.e. the neighbourhood of 50mm in 35mm-photography). This definitely is not the case with wide-angle objectives (at least if they have a retro-focus design, which is most of the time).

If the objective is not symmetric, one has to take into account the pupillary magnification, and the formula for exposure compensation is then as follows :

E = (1 + (M/P)) square

where P is the ratio of the (diameter of the) exit pupil over the (diameter of the) entrance pupil. What does this mean ? With a symmetric objective, the exit and the entrance pupil will by and large be the same, implying that P is approximately equal to one. M divided by one remains M, so the P-factor can be discarded.

If however I make a visual inspection of my 28mm wide angle objective, I can see that the entrance pupil (the side of the object) is markedly smaller than the exit pupil (the image side) (note that the P-ratio is independent of the aperture value chosen). I « guestimate » that the ratio is something like 2/1.

At first sight this seems promising, since dividing M by a P equal to 2 will substantially reduce the exposure factor, suggesting that the high magnifications you can obtain with a wide angle 28mm objective (e.g. M=5 with « only » 14 cm bellows extension) won’t become too dark, relatively speaking.

Until you realise that in such a set-up, you have to reverse your wide angle, thereby reversing exit and entrance pupil. For a M equal to 5, this will give an E equal to (1+10)(1+10)=121, which, as we saw a few minutes ago, corresponds with the exposure factor that in a symmetric objective only occurs at a M of 10.

I have to admit that I have never used a wide angle on bellows, so my conclusion is entirely based on what I « read » in the formula. If someone could corroborate the conclusion on the basis of personal experience, that would be very nice.

In the end, notwithstanding all these nice formulas, it will always remain necessary to do your own tests with your personal material. At least the formulas will give you a clue as to where to start, so you don’t have to start in complete darkness.

Affordable macro

Macro! It sounds small and expensive, how do I get started and what are the options available?

There are a few budget zooms with "macro" capabilities ranging from 28-80 zoom to 70-300mm zoom with 1:2 and 1:3 macro-focussing capabilities. They are a fraction of the cost of "real" macro lenses, but generally not durable and the quality is not always great. Nikon introduced their 80-180 macro zoom, but it is expensive! The prime macro fast lenses of 50 to 200mm ranges are excellent, but they are expensive and only give 1:1 reproduction.

There are other affordable options as well - like close focussing optics that screw in to your standard lens, extension tubes (hollow tubes that increase close focussing capability of any lens), bellows (the same principle as extension tubes), reverse rings for your standard lens and converters to a certain extent.

The good news is that you can use any combination of the above.
The drawback of close-up optical filters and reverse rings is that you can only use it for lenses with that specific diameter screw mount. Extension tubes, bellows and converters can be used with the full range of your existing lens collection.

I like combinations of converters, extension tubes, macro lenses and close focussing filters because I want far more than 1:1 reproduction. I like to fill the frame with something that is only a few mm in size. The simple rule is that the more glass you add the more quality and light will be lost.

You'll have to decide what magnification you need.
Examples:

A standard 50mm lens with a 50mm extension tube will give you 1:1 reproduction at the fraction of the cost of a 50mm macro lens. If you add a X2 converter you'll get 2,5 times the magnification. The possibilities and combinations are numerous. You can use this with the most basic SLR to the most auto-everything SLR. You'll have to use your advanced SLR in more basic modes. You'll lose autofocus, lens to camera information and most of your advance flash functions. The good news is that you do not need any of it. If you insist on keeping all the frills on your camera, your best bet is a prime macro lens. There are +1 to +6 diopter filters for your macro lens and auto- extension tube sets if you want to do more than X1 magnification.

The rest of the tutorial will concentrate on manual approach for more than X1 magnification.

Magnification:

Standard 50mm at 0,5m focus setting on the lens and the following extension tube combinations.
• 12mm extension tube => about 0,35 magnification
• 20 mm extension tube => about 0.5 magnification
• 36 mm extension tube => about 0.83 magnification
You can use combinations of above. For example 12mm + 20mm + 36mm with a standard 50mm lens would result in about 1,5X magnification. Now if you add a X2 converter you'll end up with a more than X3 magnification and should be able to focus down to 4-5cm distance between lens and subject.

Aperture:

DOF is very limited when doing macro and DOF preview button is essential (also powerful light so that you can see). You'll create a few artistic exposures with shallow DOF, but for the most part you'll need f-stops of 8-16 for most X1 magnifications. When doing X2- X4 magnification exposures this increase up to f 16-64. (Maybe one of the only virtues of converters).
Shutter speed:

With the F-stop range as discussed, it is obvious that it is going to be very slow even with faster films.

For stationary studio work this does not matter and I like to use natural daylight and reflectors with or without fill flash. You can use shutter speeds as slow as you like with your tripod and cable release. If it gets down to the 1-20sec range you can even do a bit of light painting on the subject. You'll still have to compensate for some light loss and reciprocal failure. It will differ for different lens combinations and you'll have to do a few test exposures. An easy solution is bracketing in the positive range of the exposure. If your fancy is mobile subjects, then you'll need to use flash to freeze the action.

Flash:

For moving subjects your >1/1000 flash duration would stop most action. Different cameras dictate different flash synchronisation speeds, and you can use any shutter speed below that. TTL flash:
If you use TTL exposure, you'll still have to compensate for some light loss. You'll have to make a flash bracket that allows for off camera flash placement close to your subject. If you use TTL flash, set your camera on spot or centre-weighted metering and compensate for some light loss with converters and extension tubes. TTL flash in high magnification photography often results in under exposure. Magnification of 1:1 and less does not require much, if any compensation. They also recommend the use of softboxes or diffusers with close up photography. This creates a few problems with high magnification photography. The first is that your flash to subject distance is usually a few cm with high magnification photography (see manual flash use). The second problem is that your close up lens arrangement is very prone to flare. The fun thing about photography is that even though you know disaster is pending, try it anyway.

Manual flash:

Is the GN number of your flash true or fiction from the manufacturer? You can test this by exposing 100 ISO film with a standard lens and your flash on manual, and check if the GN number is as indicated with the following formula:

Flash guide no = aperture X flash to subject distance.

Example:

GN of 16 with 100 ISO film will give a spot on exposure at 2m and f8.
This also dictates a GN 11 for ISO 50 film and a GN of 22 for an ISO200 film.

The problem is that every addition of converters and extension tubes will result in progressive light loss and you'll have to make test exposures for each combo that you use. Start by what you think the exposure should be and bracket in half stops up. Once you know how much light loss each combination costs you in stops, write it down and you are set for fun. My memory is short and I misplace most things that I write down, so I guess my light loss most of the time. Converters will increase your f stop by the factor of conversion. Each 1mm of extension tubes correlates with an exposure factor of about 0,1.

Example:

A 20 mm extension tube correlates with an exposure factor of about 2, or opening up 1 stop.

If you use TTL you can add 0.15 times the magnification for compensation. This is just a rough guide that I use for my Nikon set-up and I am not sure if it would be applicable for other systems.
The bottom line is do not give up and make test exposures and get to know your equipment.

Focussing:

Decide what magnification you need and set-up your simplest lens arrangement at the minimum focussing distance. Focus is achieved by varying the camera to subject distance. There is no room for autofocus in high magnification photography. A few mm movement is all that is needed. You can appreciate the problem of finding a fast moving bug in the viewfinder, let alone keeping up with it and focussing on it.
Sorry this got a bit out of hand and should solve problems with insomnia if you got this far without falling asleep. I wrote this mostly from memory and personal experience. Feel free to question and disagree as I usually make mistakes. I could continue this with specific examples of problems of macro shots and how to avoid it. Feedback would be appreciated, as I would like to avoid boring you to death.

Message edited by author 2005-09-07 09:25:37.
09/07/2005 08:55:17 AM · #15
Yes it is unfortunate the DOF is sooooooooo thin. I have pulled out a large amount of hair fighting with this problem. One thing that helps a bit is using the smallest apperature you can manage this will give you a slightly larger DOF. As a general rule the greater the magnification the thinner you DOF will be. There realy is no way around this that I know of. Even using close up lenses you will have a shallow DOF granted it will not be quite as extreme. I have had to rely on magapixils and cropping to get the DOF I wanted on several occasions. Is there a cheep way to get macro? yes and no. Yes there are cheap methods of macro. But they will not alow you to escape the 1:1 barrier, or if they do not by much. The exreme close ups like the one you posted and some others in this mentorship unfortunately require a fair amount of pricey equipment. In the next lesson I will post in a bit. I will go over some camera settings. I think a few of the formulas might help you a bit with some of the problems you noticed.

09/07/2005 08:39:42 AM · #16
I gave the reverse lens technique a try:

This is an edited but uncropped version.
I am baffled by the hairthin DOF - so to say, because it's actually thinner than a hair! I couldn't even manage to get all of the head into focus.
I feel that this is a really limited method, because it's impossible to get anything into focus in an uncontrolled environment. Increasing the aperture resulted in awful vignetting.

I guess I'd rather be interested in close-up lenses, to take pictures of butterflies and such, like spurs did. The only ones I found cost about 90$. Am I looking at the wrong stuff or is this the price I have to expect?
08/30/2005 08:02:33 AM · #17

Not the greatest but I work with cheap glass, can't really afford anything nicer right now so I have to work with what I have. One day.
08/25/2005 07:50:23 AM · #18
I will try to comment on every photo submited to this section. (so long as it is one of your own bug macros). Thanks zippy and Jaimeson for the encouragement. I was begining to feel like I was loosing everyones intrest. And zippy feel free to post any questions on the forum or e-mail me. I would be more than happy to explain any part of the lesson. This goes for anyone else I may have confused in my rambling as well. So keep those bug shots comming the next lesson will not be until Tuesday. This should give everyone all weekend to hut for those bugs and get them posted. I will however be commenting and answering any questions until then.
08/24/2005 08:57:03 PM · #19
I was so excited when I read this lesson plan. I couldn't wait to get outside and start taking pictures. Thanks so much for mentoring us in this great subject!

Photos were taking using the Super Macro function in manual mode.

08/24/2005 06:55:39 PM · #20
Troy, thank you for the bug lesson. I am very interested in bug shots. I frequently follow them around my yard taking pictures. I have an abundance of Gulf Fritillary Butterflies that like my passion flowers. I think a lot of this lesson went over my head. I will reread it a few times and hopefully will understand more as time goes on. I have a macro lense (Canon 100mm f2.8 USM Macro) and I am often disappointed in the focus in my shots. I usually use a tripod when I use the macro lense. I also shoot in AV mode and I try a range settings to see how various DOF will look.

Your bug shots are really great!


08/24/2005 02:36:11 PM · #21
Now if I can only find some bugs :)
08/24/2005 02:34:10 PM · #22
comments are welcome.. this is just a shameless request and a bump.
08/24/2005 08:17:45 AM · #23
BUGS!!
Lesson 3

I had a lot of fun taking photos for this section of the lesson. I just wanted to start with a thank you, for giving me a good reson to have such a great time shooting for this mentorship.

Bugs!!! (Insect Macro Photography)



Introduction
I am a artist through passion. I had started scanning images back in 1994 for inspiration for my art. I bought a digital camera in 2000 for family photos and to document my art work. The camera wasn't as good as I would have liked for the latter due to the slow auto focus and other camera specific limitations. I like the digital, though, because it makes it easy to try something and immediately see if, and how, it worked.
When I first got the camera, my (then) 5 year old nephew came into my home office one day and suggested I photograph a bug that he had his eye on and we did. It was worse than terrible by my current standards, but it did allow us to see the bug in more detail than we could in real life. That is what got me started and what I enjoy so much about macros. They let you see what you ordinarily cannot. As a engineer, I am quite curious by nature. I kept shooting the bugs, had fun, and my camera was reasonably good at it. I also liked that as I developed skills shooting bugs, all of my other photos (dogs, family, etc), got better too.
The Internet, DPC and photo forums have been my photography teacher. Thus, I am especially thankful to those who have given me honest and constructive critiques. I guess my dream is that one day my images will appear in homes around the world whether they are drawn by hand or shot with a camera matters not to me anymore.
I am Teaching this mentorship because when I show my images, people often ask how I do it. So I am going to try and tell you. Keep in mind that I am just a self taught amateur who is willing to experiment and has an insatiable curiosity. Thus, the internet acronym "YMMV" applies (i.e., "Your Milage May Vary"). Nonetheless, I hope this information is useful to you and enables you to have more fun taking and creating images.



Philosophy
Most of my bugs are photographed in the natural environment. I don't chill them, or spray them, or glue them, or nail them down. I will sometimes move some blades of grass or vegetation to get a better view. Even less often, I will try to relocate the bug to a new location. Nonetheless, they are always alive and well when I shoot them.
Occasionally I will shoot the critter on a building (white ones especially) or other man made structure. I especially like white buildings, because I can overexpose a bit and remove any remnants of the building in the digital darkroom giving the image a clean, studio-like quality.
My goal when photographing the bug is to present it in a positive light; to show it at it’s best. I especially like intimate portraits, behavior shots, and full body shots with clean and smooth backgrounds.



Using Close-Ups (Diopters)
A close-up lens (or diopter) enables the camera to focus closer than it normally can. This means that the image will appear larger in the frame because you can get closer to it. In other words, close-ups allow you to magnify the image. A diopter is, in fact, a magnifying glass.



Close-ups can be stacked. When doing this, the highest powered close-up should be the closest to the camera. I have stacked as much as +27. One problem with stacking is that the quality decreases because there is more glass and more light abnormalities and distortions occur. Another issue is that as the magnification increases the depth of field (DOF) decreases. With really high magnifications, the DOF becomes paper thin.
Still another important issue with close-ups is that you need to get so close to the subject. The distance from the camera’s lens to the bug is called the "working distance". One of the techniques I use to increase working distance is to follow the close-ups with a 2xTC. In addition to the increased distance making it more likely that I can get the shot (by not disturbing the bug), it also makes it easier to get better lighting. A disadvantage of the 2xTC, though, is that some magnification is lost.

I have learned to try various “optical marriages”, because some lens combinations work well together and others don’t. For example, I tried diopters after the 2xTC, but the results weren’t very good. It was a poor "optical marriage".



Reversing a Lens

While stacking bunches of close-ups gave me some great shots with good magnification, I wasn’t really satisfied with the technique. I found that stacking more than 2-3 lenses wasn’t really worth it, since I rarely could obtain the quality I desired.
I had read about a technique involving reversing a lens to gain magnification here on DPC.
To do this, you first need the lensmate adapter, followed by a macro coupling ring (which has male threads on both sides). This permits you to reverse the lens and attach it to the macro coupling ring, by it's filter threads. Links to where you can find this equipment were presented in the previous section on camera equipment.
I first tried this technique with a Canon 35-80mm F4.5 lens, but the vignetting (i.e., a black circle like frame on the image) was prohibitive. So I went to a camera store with my camera to check out the 50mm (i.e., normal) lenses. I wound up buying a Pentax 50mm F1.4 lens. The F1.4 means that it is a fast lens (i.e., it lets in a lot of light). With the G1, there was minimal vignetting (a slight darkening of the corners) and with the G3's increased zoom, there is none.
Folks often ask me questions about which is the best 50mm to reverse. My advice is to do what I did and go a camera store and try out some lenses. In other words, you have to see for yourself which "optical marriage" will work. For just trying out a lens, you can just handhold it in the reverse position in front of your fixed lens (rather than bothering with the macro coupling ring).

The reverse lens acts as a powerful (about +25) and high quality diopter. I have to be about 1.5 or so inches from the bug with this setup. Also, you will typically need to use full zoom to avoid vignetting. I set the 50mm to its widest aperture (in the case of my Pentax it is F1.4) and set the focus to infinity. Then I do the rest with my camera.



Camera Settings

Here are some tips:

1. Use manual focus. Lock the focus and then gently rock the camera back and forth until you find that sweet spot (where the image looks crisp in the LCD). This takes a lot of practice.

2. Use full zoom in situations were vignetting is likely (e.g., if using a 2xTC after some stacked close-ups or using a reversed 50mm lens).

3. Use a small aperture (large F value) to maximize depth of field (the amount of the image in focus). The more magnification, the less depth of field.

4. Fill flash is usually a good idea. The majority of my shots are at F8 (which is the smallest aperture a prosumer digital camera gives) with fill flash.

5. I typically use aperture priority (Av) with F8 (the smallest aperture my camera gives).

6. I also use manual mode a lot. On the G3 it enables higher shutter speeds with F8, but the quality of light is different and the backgrounds are often darker.



Lighting & Flash

Here are some tips:

1. Shoot on bright days so you can get a decent shutter speed. Bright overcast days are expecially good.

2. If you can afford an external flash, it really makes a dramatic difference. It gives a lot of flexibility and control.

3. If you do use flash, it needs to be diffused (e.g., a tissue) or bounced (e.g., off a white card or reflector). Pointing the flash indirectly is another possibility.

4. The 2xTC after the close-ups can help with lighting since it is easier to illuminate the subject more evenly from a distance.

5. A butterfly bracket (and off shoe cord) for the external flash will give you even more control of lighting.

6. Varying exposure and/or flash compensation as well as the position of the external diffused flash (bounced or straight on), gives even more flexibility still.

7. If the bug gives you the opportunity, try various possibilities.



Tripod or Not?
About 90% of my bug shots are handheld. I think this is one of the major advantages of a prosumer digital with a flip out LCD screen. When I do use a tripod, I may use a macro focusing rail (or slider) that allows you to move the camera back and forth in tiny increments without moving the tripod. Given that the DOF is so shallow in macros and that I prefer to lock the focus and move the camera back and forth, the rail is a useful tool.

As I noted above, most of my shots are handheld. As such, I have become quite good at steadying the camera. I do this in a number of ways. I will often lean against a tree or fence. I keep my elbows in and often squat bracing the camera against my knee/leg. If I can, I will rest the edge of the camera on a log or other available structure. I also either put the camera cord around my neck or in my teeth and push the camera away from me when I shoot. I sometimes play with monopods.



How to Get Close
The philosophy I discussed earlier is relevant here. To me, photographing bugs is like hunting big game. You have to work for that trophy and being able to track and stalk the game are skills that the hunter develops.
I especially enjoy dragon hunting, although over the years, I have grown find of all the different flies. I don't go out at special times and I am not a morning person. I have about 3 acres that are about 15 minutes from a river and there are some marshlands in between. This, I am told, is why I am inundated with dragons at certain times of the year. Water seems to be a key when it comes to the dragons.
Here are some tips for getting close:

1. Go slow. Be patient. Watch the bug for awhile to see how it behaves.

2. Some of the bugs are more tolerant than others (both across species as well as within).

3. Move slow. Try not to caste your shadow on the bug. If the bug takes off, be still and wait a minute or two, it will often return to the same perch.

4. Different optical marriages and setups give you different working distances. Be sure to try out the various possibilities.

5. When you find a bug that lets you get close, start firing that shutter like a maniac. Be prepared, such that all settings are as they should be, because you may only get one shot.

6. As you master the focus and exposure, you can start looking for cleaner backgrounds and pay more attention to composition (placement of the bug in the frame).



The Digital Darkroom
The more the magnification, the less DOF you get. There is no getting around that. I try to use what little I get as best I can. Furthermore, I try to take the image such that it will not need much “developing” in the digital darkroom. In reality, I find that such perfect images are few and far between.

When working in the digital darkroom, my goal is typically not to alter the image, but rather to improve upon what the camera gave me. Occasionally though, I will alter the image by adding clouds to the sky, cloning away unwanted items, or in rare cases, replacing the background.

I have also worked on a technique of using more than one image (taken within seconds) that have different planes of focus and compositing them for increased DOF (I am most likely to do this with extreme macros because DOF is so limited there). The milkweed beetle shown here is an example.

Here are some digital darkroom tips:
1. Take a lot of shots, trying to vary the plane of focus a bit on each so that you are likely to get a couple that hit the sweet spot so to speak.

2. Get used to deleting most of the shots you take. As you gain skill, the hit rate goes up a bit (sometimes).

3. Rotating, cropping, adjusting the levels curves, saturation, and contrast, as well as sharpening the subject and blurring the background are the basics of developing the image.

4. Masking is hiding areas of the image, so that you can work on other areas without affecting the hidden areas. Typically one might mask the foreground so that the background (BG) can be worked on. I typically do this so that I can give the BG a bit of a blur to remove digital noise (since I don't have one of the high end digital SLR's that give relatively noiseless backgrounds). Creating a mask can be tedious and can be done lots of different ways. I like the "magic wand" tool that selects similar areas on the basis of color. I typically use that first and then refine the mask with other tools.

5. Another tool I have found find useful in the digital darkroom is a graphics tablet, which allows me to use a pen instead of a mouse to control the cursor. I am currently in the market for a new one. My old one died about a year back.

So for this sections mission (i'm sure you never saw this one comming) lets see some bugs. Go out and get some bug portaits. Best of luck to all of you. Just remember be patient and have a great time.

Message edited by author 2005-08-24 08:22:10.
08/23/2005 07:36:30 AM · #24
It would apear I deleted the larger images for the last section. My apologies. I will make sure the next section has nice big photos. So are there any questions before we move on to the next section? The next section is titled BUGS!! we will be going over how to photograph a bug. We will also be using a large number of the camera settings and other things we have gone over so far in this mentorship.
08/23/2005 07:32:53 AM · #25
Nicely done Digital Quixote. Thank you for posting all of the camera settings. This should help other better understand a few of them.
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