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12-07-2019, 09:16 AM - 1 Like   #16
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For more magnification, try a reversal ring. The setup is ugly but it works.


This what it looks like - the one below was an official Pentax product. I have one.





There is a 49mm filter ring on the other side. Wide angle lenses give more magnification, AFAIK. The wider the better.

Combine this with a bellows for yet more magnification.

Actually, the Pentax bellows lets you mount the lens in reverse, so you don't need an adapter. But if you have one, you can use the maximum extension of the bellows.

12-07-2019, 09:18 AM   #17
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QuoteOriginally posted by Liney Quote
I tried something similar a year or so ago using a metal ruler and various combinations of lenses and extension tubes. I'd been googling magnification factor and came up with a formula for working it all out based on the width of the observed image. Of course using a metal rule and a bit of jiggling around to get it in focus would give me the width of the observed image, and then putting the data into a spreadsheet gave me the magnification.

I ended up with a table for all my lenses and the combination of extension tubes, which was great at the time but seems to have been mislaid. Shortly after that I bought my bellows, so I suppose I can go back and do the whole thing again.

One thing I would suggest though is you try it again with the extension tubes and the teleconverter, do it one way (teleconverter then tubes} and then try it the other way {tubes then teleconverter}. I read somewhere that it will make a difference, it comes down to the distance from the teleconverter to the sensor.

Actually I think I want to go and try my bellows and the extension tubes together, see what sort of results I get from that. If I can find my teleconverter too this could be fun.....
Experiment done. I put the extension tube at the back and it gives me the about 4.6x mag as above, focus distance 1.7cm (ish) However, when I put it at the front -with the three tubes behind next to the body- I am a much further 3.5cm away at a sacrifice of about 0.8333x the 4.6 mag I get the other way. Translates to about a full mm of mag. A lot when you consider the size of snowflakes but is the same amount as picture #3 at a further distance, so better for lighting. I may play around with it's position in the rig even more. maybe it works best behind one tube, but in front of others. This is kind of fun. Not to mention it provides us more to discuss than some obscure lets raise the post count discussion.

---------- Post added 12-07-2019 at 08:19 AM ----------

QuoteOriginally posted by Wasp Quote
For more magnification, try a reversal ring. The setup is ugly but it works.


This what it looks like - the one below was an official Pentax product. I have one.





There is a 49mm filter ring on the other side. Wide angle lenses give more magnification, AFAIK. The wider the better.

Combine this with a bellows for yet more magnification.

Maybe I'll get a reversing ring for my 14mm... or the 16-45mm, or the 18-55...

---------- Post added 12-07-2019 at 08:29 AM ----------

Wouldn't you know it. Putting the teleconverter in the middle with 36mm extension in front and 36mm behind it offers the full 4.6x magnification at 2.5mm from the lens. Winning combination for this setup I think.
12-07-2019, 02:20 PM - 1 Like   #18
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Sounds like you're having fun!

I don't know what setup you're using in terms of lighting but having the teleconverter in there is going to knock off a couple of stops of lighting, if you are shooting snowflakes I assume the exercise will be in getting enough light but not too much heat.

The reversing ring is a good idea, I've got one and have tried it on a couple of occasions but it is a pain in the neck if the lens doesn't have an aperture ring. A non-engineering lump of blutac was applied to get the aperture to a point that gave me enough DoF.

Of course the next step is the bellows. I did my calcs and with a 50mm lens and full extension I could get around x3.6 magnification. I haven't tried the extension tubes with it yet but plan to over the holiday period
12-07-2019, 05:09 PM - 2 Likes   #19
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QuoteOriginally posted by Liney Quote
Sounds like you're having fun!

I don't know what setup you're using in terms of lighting but having the teleconverter in there is going to knock off a couple of stops of lighting, if you are shooting snowflakes I assume the exercise will be in getting enough light but not too much heat.

The reversing ring is a good idea, I've got one and have tried it on a couple of occasions but it is a pain in the neck if the lens doesn't have an aperture ring. A non-engineering lump of blutac was applied to get the aperture to a point that gave me enough DoF.

Of course the next step is the bellows. I did my calcs and with a 50mm lens and full extension I could get around x3.6 magnification. I haven't tried the extension tubes with it yet but plan to over the holiday period

For now natural light is what I've been using and I'm completely sheltered from wind, so longer exposures are fine. I've tried a ring light which might be ok if I can get the angle to work. Without the proper angle, the snowflake is rendered transparent. In fact, that's the main reason I use natural light; I can get that angle a whole lot easier than trying to use unnatural light. But yes, not only does the teleconverter darken things, but the extension tubes do too. However, this way, with the teleconverter at the back I get more magnification than straight up extension tubes AND I am pushed further back = more light.

12-07-2019, 05:28 PM - 1 Like   #20
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You've got me wondering how it will turn out now, I'd try it myself but we don't get snow......
12-07-2019, 09:41 PM - 2 Likes   #21
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This was a test the other day with frost. Should be decent as long as I get some good flakes. but it needs to snow first.

12-07-2019, 10:09 PM - 1 Like   #22
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Very nice

How I go about doing snowflake work now is using a 50mm lens that is then reverse mounted to a 70-200 along with a 1.4 tc and extension tubes.

I find the best snowflake shooting weather is really not what I would consider snow but the fog with ice crystals that lingers around without any wind as this can create abnormal snowflakes and I also find it the smaller flakes that are most please and uniform

The snow fall that most would think of using for snowflake work really produces what I would consider ugly flakes as they can be formed and melted and reformed creating not so pleasing flakes as it passes thru the different air currents . Also you will get much lager flakes that you would typically see in a snow fall are clumps that as they fall down to earth collect more and more together the closer the get to the ground.

What I find best is during that low lying fog where they are being formed early and without much temperature changes and breezes as this can distort their formation. Most of the time this is during a clear night and as the temperature decreases these crystals form near to ground level. If you have a good chance of fog then you might want to consider collecting these as they fall to earth .
12-08-2019, 09:46 PM   #23
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QuoteOriginally posted by aitrus3 Quote
For now natural light is what I've been using and I'm completely sheltered from wind, so longer exposures are fine. I've tried a ring light which might be ok if I can get the angle to work. Without the proper angle, the snowflake is rendered transparent. In fact, that's the main reason I use natural light; I can get that angle a whole lot easier than trying to use unnatural light.
I usually like to use a 2 to 3 different light sources . one to add color usually coming in from behind and then a second from the side, this can give you shadows along the edge of the flake while giving highlights along the other surface.
When lite from above and from every angle from above you will lose a lot of the surface variations of the flake

12-09-2019, 04:29 AM   #24
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QuoteOriginally posted by Ian Stuart Forsyth Quote
Very nice

How I go about doing snowflake work now is using a 50mm lens that is then reverse mounted to a 70-200 along with a 1.4 tc and extension tubes.

I find the best snowflake shooting weather is really not what I would consider snow but the fog with ice crystals that lingers around without any wind as this can create abnormal snowflakes and I also find it the smaller flakes that are most please and uniform

The snow fall that most would think of using for snowflake work really produces what I would consider ugly flakes as they can be formed and melted and reformed creating not so pleasing flakes as it passes thru the different air currents . Also you will get much lager flakes that you would typically see in a snow fall are clumps that as they fall down to earth collect more and more together the closer the get to the ground.

What I find best is during that low lying fog where they are being formed early and without much temperature changes and breezes as this can distort their formation. Most of the time this is during a clear night and as the temperature decreases these crystals form near to ground level. If you have a good chance of fog then you might want to consider collecting these as they fall to earth .

Thanks for that. I've been trying this for several years and definitely know the best flakes come not necessarily from the biggest clumps falling down. However, I've also spent a lot of time catching snow as it falls and studying it very closely. Patience is a virtue of mine and I can easily spend hours in a snow fall catching flakes as they come down. I've caught the best flakes this way. What started out as frosty uneven flakes, turned to spheres and a couple cycles of this, then all of a sudden I started catching some of the best flakes I've ever seen.


As for lighting. I've since been in contact with a master snowflake photographer who strictly uses a ringflash. The lighting very much depends on the angle the snowflake is to the source, and no matter what source that is there is only a 5 degree window where you get the best reflected light. Natural has been my goto because it's really easy to find that angle with a constant source of light. With a flash, you'd have to take a shot, adjust, take another shot and adjust some more... it could take a real long time. To be clear, while I like images of snowflakes lit from behind that are transparent but side lit to show some details, I personally like opaque shots better, like this: Don Komarechka Photography added a new... - Don Komarechka Photography | Facebook
12-09-2019, 07:34 AM - 1 Like   #25
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QuoteOriginally posted by Liney Quote
One thing I would suggest though is you try it again with the extension tubes and the teleconverter, do it one way (teleconverter then tubes} and then try it the other way {tubes then teleconverter}. I read somewhere that it will make a difference, it comes down to the distance from the teleconverter to the sensor.
Flipping the order of the tubes and teleconvertor makes a HUGE difference. For highest magnification, the best order is: lens + extension + teleconvertor.

The math for the expected magnification is pretty simple.

Extension tubes and bellows ADD to magnification but don't change the focal length. The amount of added magnification depends on the focal length of whatever is in FRONT of the tubes. It is higher for short focal length lenses. The exact amount is L/F where L is the length of the extension or bellows setting and F is the focal length in front of that. Thus, a 50mm macro set for 1:1 has magnification of 1 and if you add 72 mm of extension tubes, that adds 72/50 = 1.44 to get a total magnification of 1+1.44 = 2.44.

Teleconverters MULTIPLY the magnification of what is FRONT of them and also MULTIPLY the focal length for purposes of what's attached BEHIND them. Thus, a 2X teleconvertor makes any extension tubes behind the teleconvertor add 1/2 as much magnification as tubes in front of the teleconvertor.
12-09-2019, 11:14 AM - 1 Like   #26
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QuoteOriginally posted by photoptimist Quote
Flipping the order of the tubes and teleconvertor makes a HUGE difference. For highest magnification, the best order is: lens + extension + teleconvertor.

The math for the expected magnification is pretty simple.

Extension tubes and bellows ADD to magnification but don't change the focal length. The amount of added magnification depends on the focal length of whatever is in FRONT of the tubes. It is higher for short focal length lenses. The exact amount is L/F where L is the length of the extension or bellows setting and F is the focal length in front of that. Thus, a 50mm macro set for 1:1 has magnification of 1 and if you add 72 mm of extension tubes, that adds 72/50 = 1.44 to get a total magnification of 1+1.44 = 2.44.

Teleconverters MULTIPLY the magnification of what is FRONT of them and also MULTIPLY the focal length for purposes of what's attached BEHIND them. Thus, a 2X teleconvertor makes any extension tubes behind the teleconvertor add 1/2 as much magnification as tubes in front of the teleconvertor.
Thanks for that, however, as you can see with real world experiments I get the most magnification at the furthest focus distance with the teleconverter in the middle of the two 36mm of extension. With it in the middle, I get the max mag possible at a distance of 2.5cm away. With it at the rear of everything I get my max possible magnification but at 1.7cm distance. So in this case it's not best to have it at the rear, but in the middle. Further back = more light.
To put it plainly: with teleconverter behind everything, I get a total of 5mm of the ruler visible in the frame but at 1.7cm distant. With it in the middle I get a total of 5mm of the ruler visible but a total of 2.5cm back.

---------- Post added 12-09-2019 at 10:32 AM ----------

Proof is in the pudding. The Teleconverter between the 72mm.

12-12-2019, 05:38 AM - 1 Like   #27
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This is what an SMC Pentax M 20mm lens f/4 on a reversal ring plus 12mm, 20mm and 36mm extension tubes can give you.



You are looking at the markings on a metric plastic ruler. That's about 4mm from side to side. It was taken with a Samsung NX1. The APS-C frame is about 24mm, which gives a magnification ratio of six to one. Not bad.

Something a little less abstract:



Apologies for the slight softness in focus. Depth of field is almost non existent. The rig doesn't make it easy to set focus. One can tilt the tripod or move the subject and it's not easy. To things worse, the lens tends to unscrew when you turn the aperture ring.

My bellows with focus rail will make things easier in the focus department. It will also give me more extension for even more magnification. I will get back to you on that.
12-14-2019, 02:06 AM   #28
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Jut out of interest I had a quick play today based on information form this thread. I have a set of bellows, set of extension tubes, and a two times telconverter. Changing the order around I managed to get the following "magnification":

Camera body, bellows at full extension, teleconverter, 38mm extension tubes, 50mm lens - about 4mm across the width of the viewfinder.
Camera body, teleconverter, bellows at full extension, 38mm extension tubes, 50mm lens - about 2 and a bit mm across the width of the viewfinder
Camera body, teleconverter, bellows at full extension, 38mm extension tubes, 28 - 80mm lens on a reversing ring (i only have one reversion ring and it doesn't fir all my lenses} - about 1.1 mm across the width of the viewfinder.

A couple of problems, the focal distances were rather erratic and the DoF was miniscule, plus to get a decent image I would need some serious lighting....
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