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Roadwart · Post by **Roadwart** » Mon Mar 30, 2009 5:25 am

Just thought I`d say "Hi"

I was directed here by a mate (Hi Laurie) after seeing some of his shots.

Heres a link to my first attempt at stacking.

http://www.cyprinoid.demon.co.uk/macro/ ... pstack.jpg (Link posted as I can`t recall if the image is small enough to post here directly.)

26 image stack. EOS 400D tripod mounted tamron 55-200 coupled to a reverse mounted OM 50mm f/1.8.

Colour looks a bit off as I`m using a halogen desk lamp for now coupled with a homemade flash snoot/diffuser but I can always say I sepia toned it

I look forwards to any comments you may have.

rjlittlefield · Post by **rjlittlefield** » Mon Mar 30, 2009 11:11 am

Roadwart, welcome aboard!

A friend of Laurie's, eh? Well, you can't do much better than that, if you're interested in stacking.

Yes, your image would have been too large. We only allow 800 pixels max width & height. Other rules & guidelines are posted HERE

The image looks like a good start on stacking, but there are some obvious opportunities for improvement.

For something as big as a cricket head, I'm thinking you should be able to get a lot more depth and a lot sharper detail from a 26-frame stack.

What comes to mind is that maybe you're working with too wide of an aperture. What I see could be explained by running that reversed lens at its full f/1.8, and not stopping down the rear lens either.

Whenever you set up a new lens system, the first thing to do is to shoot a series of images with apertures ranging from full open to f/16 or so. This is not a stack, just a set of single frames.

Then, poke through the series looking closely at image quality. Find the one or two that have best resolution. Chances are, they'll be a couple of stops down from wide open. If one image is clearly better than the others, then choose it. If more than one are about the same, then choose the one with the smallest aperture. That will give you the most DOF per frame, which makes life easier.

Now that you know the best aperture, you need to figure out a good focus step. That's easy -- just shoot a short stack with a focus step that's a lot smaller than you really need. Then poke through that stack to determine how far apart two frames can be and still have at least some detail that is sharply focused in both frames. The focus step between those two frames is what you want for the full stack.

After you know the best aperture and the corresponding focus step, then it's time to shoot the full stack. I think you'll be pleasantly surprised by how much difference this tuning can make.

Again, welcome to the forum! We look forward to seeing a lot more of your work.

--Rik

Roadwart · Post by **Roadwart** » Mon Mar 30, 2009 1:56 pm

Thanks for the kind words of welcome & encouragement. Rules & guidelines read, thanks for the link, & ready to take part in this fascinating hobby.

I`ve know Laurie since primary school & he`s the guy I credit for getting me into photography in the first place.

The reversed lens was stopped down to f/16 but the tamron was wide open at F/5.6. I`ll use your calibrating method & see what works best. Then I just need to sort out my lighting & the next attempt will be hopefully alot more pleasing.

rjlittlefield · Post by **rjlittlefield** » Mon Mar 30, 2009 2:13 pm

Roadwart wrote:The reversed lens was stopped down to f/16 but the tamron was wide open at F/5.6.

Hhmm... I'm having trouble matching what I see against that description. That could just be a problem with my eyes. But it could also be that the equipment didn't actually do what you thought you told it to.

The next time you fire up the gear, pretend you're the subject, look into the front of that reversed lens, and make sure that it's really stopping down. With some lenses, it's not enough to just set the aperture ring.

--Rik

Roadwart · Post by **Roadwart** » Mon Mar 30, 2009 3:37 pm

Its def stopping down. There`s a little lever that moves that has to be wedged open for the aperture to activate which I did wedge. The guys in the camera shop warned me I`d have to do that when I told them what I was going to do with it.

Had a bit of a play tonight & did much better with both lenses at F/8.

13 images in this one & a huge improvement already!

Some of the fuzziness is down to my cobbled together set up but if I keep improving I`ll be able to justify spending out on some better equipment. I`m already trawling ebay for microscope focus racks.

lauriek · Post by **lauriek** » Mon Mar 30, 2009 4:52 pm

Hello mate!

Ahh now the woodlouse is looking much, much better, in fact I can't really see anything wrong with it at all.. (Some would complain it's slightly off horizontal but that doesn't bother me, I quite often use 'off' angles..)

You might now want to try opening up the zoom lens a little, if you can shoot finer slices with your current movement... It's hard to tell if this would help from the 800px shot here but it might get you a tad of extra sharpness at full res...

rjlittlefield · Post by **rjlittlefield** » Mon Mar 30, 2009 8:53 pm

This is much better!

Might benefit from a bit more fill illumination on the left side, and perhaps a tad more diffusion overall, but these are mostly artistic points. It looks to me like you have the technical aspects pretty well in hand now.

I do have one question about the illumination. It appears to me there are white specular reflections from a source at upper right, and blue specular reflections from another source directly above. I presume the white is a lamp of some sort. What's the blue?

--Rik

Roadwart · Post by **Roadwart** » Tue Mar 31, 2009 3:32 am

Thanks guys! I can now sort out the finer stuff once I`ve done a proper aperture test to see which settings work best for that lens combination.

I think the white flecks are burn out as the RH light source wasn`t diffused. The blue flecks I can only surmise are reflections from the TV as I took those shots in the living room while the Mrs was watching TV.