salutations from argentina!

Lets get to know each other better. Here's a forum to post images and short autobiographies of ourselves as well as any other info you would like to post about yourself.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

Carmen
Posts: 275
Joined: Tue Feb 10, 2015 10:32 am
Location: Buenos Aires
Contact:

salutations from argentina!

Post by Carmen »

Esteemed Micro-photographers:

:D hello! my name is Carmen and I live in Buenos Aires, Argentina. My husband and I are nature lovers. He is more interested in birds. The birds of argentina are beautiful and intelligent. I admire the birds, but am more interested in photographing small things, which is an unusual, though respectable, hobby here in argentina.

Over the years, I have acheived some success with macro lenses. And Last year, succeded at focus stacking. But like other before me, I slowly became aware of the limits of my humble equipment. Thus I investigate ways and means of photographing our beautiful local plants and insects in even more detail.

I have read some of Savazzi's relevant on line material, perused coinimaging.com, Kreb's Microscope Objectives on Camera Bellows, and more general information about microscope optics. I then discovered this noble forum and many inspiring insect microphotographs. I read the informative FAQ: How can I hook a microscope objective to my camera? I concluded that a target range of approx' 4 to 5x with reflected light is quite likely feasible, and continue to investigate microscope objectives as most appropriate means to this end.

I really value this forum as a platform for mutual support. I feel optimist that I can learn much, and hope to support others interested in amateur micro-photography to the extent that my level of skill and experience merits.

sincerely
:D

rjlittlefield
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Location: Richland, Washington State, USA
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Post by rjlittlefield »

Carmen, welcome aboard!

I'm the fellow who wrote that FAQ, so I'm very glad to hear that it's helpful. Yes, 4X to 5X with reflected light is pretty straightforward. You just need a focus stepping mechanism that is precise enough to handle the shallow steps that are required.

One of my favorite examples at 5X on an APS-C sized sensor is the blowfly at http://www.photomacrography.net/forum/v ... hp?t=16348. That was shot with a 10X objective, using a shorter than normal tube lens to reduce the magnification. The amount of detail captured by these objectives is quite astonishing.

We look forward to talking with you further. :D

--Rik

Carmen
Posts: 275
Joined: Tue Feb 10, 2015 10:32 am
Location: Buenos Aires
Contact:

Post by Carmen »

Thank you rik for the kind welcome!

The microphoto you pointed out is very impressive! Wouldn't a shorter than standard extension tube increasing working distance?

I trust you understand why I would like to endeavor toward similar results with local insects (dragonflies, beetles...)

very impressed by this forum, a truely worthwhile Project!

warmest regards from argentina!
:D

Harald
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Joined: Fri May 13, 2011 10:33 am
Location: Steinberg, Norway
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Post by Harald »

Welcome to this great forum Carmen :D
I have learned a lot from all the great people in this forum, there are a lot of knowledge and skills here.
I use my microscope in the winter to photograph crystals in polarized light. In about 3 months, the field macro season starts here in Norway.

Hope to see some great images from you in the near future. :P
Kind Regards
Harald

Lier Fotoklubb / NSFF
AFIAP / CPS
BGF / GMV
http://www.500px.com/blender11

rjlittlefield
Site Admin
Posts: 23561
Joined: Tue Aug 01, 2006 8:34 am
Location: Richland, Washington State, USA
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Post by rjlittlefield »

Carmen wrote:The microphoto you pointed out is very impressive! Wouldn't a shorter than standard extension tube increasing working distance?
You're thinking in terms of finite objectives. Yes, with a finite objective you can shorten the extension tube to get lower magnification and greater working distance. However, the image quality may degrade as the objective is pushed away from the focus distances that it was designed for. In addition, we've never found a finite 10X objective that can be pushed much below 7X without having the corners go bad because the useful field width of the objective is too small. So, that particular image could not have been made with a finite 10X pushed down to 5X.

The objective used in that thread is infinite, and it's one of the modern designs that has much larger useful field width than any of the older finite designs. As explained in my reply in your other thread, an infinite objective has to be used with a tube lens or the image will degrade from aberrations. However, the length of the tube lens can be changed without introducing aberrations, so then the only concern is whether the field width is large enough to cover the sensor with high quality image. With this 10X objective, that's true down to about 5X on an APS-C sized sensor.

The use of this objective in this manner -- 10X pushed down to 5X and still covering the whole APS-C sensor -- is a good illustration of what I'm talking about in the other thread when I say "so to take advantage of modern design methods and materials, infinite is the path to absolute best quality."

That said, if I had imaged the blowfly at 4X or 5X using a finite objective designed to work at those magnifications, it would have looked pretty good too. Just not as good. In exchange, the 4X or 5X would have a much smaller aperture, which would have allowed a much larger step size than the 10 microns (0.010 mm) that I had to use with the 10X objective.

It could very well be that for your purposes, you would be better off to use finite objectives on empty extension tubes at or near their rated magnifications. I'm sure we will talk more about this, but let's do it over in the Technical forum.

--Rik

Carmen
Posts: 275
Joined: Tue Feb 10, 2015 10:32 am
Location: Buenos Aires
Contact:

Post by Carmen »

thank you harald for the warm welcome! :D Winter your way, but summer here and australia. Woiuld love to see your crystals!

I agree with your favouable characterization of forum.

but I have much to learn before the puchase of equipment -cannot afford mistakes! :wink:

cheers
:D
Harald wrote:Welcome to this great forum Carmen :D
I have learned a lot from all the great people in this forum, there are a lot of knowledge and skills here.
I use my microscope in the winter to photograph crystals in polarized light. In about 3 months, the field macro season starts here in Norway.

Hope to see some great images from you in the near future. :P

Harald
Posts: 678
Joined: Fri May 13, 2011 10:33 am
Location: Steinberg, Norway
Contact:

Post by Harald »

Hi there Carmen,

Here is one of my crystal images:

http://www.photomacrography.net/forum/v ... highlight=
Kind Regards
Harald

Lier Fotoklubb / NSFF
AFIAP / CPS
BGF / GMV
http://www.500px.com/blender11

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