Joined: 06 Apr 2010
|Posted: Thu Apr 08, 2010 9:05 am Post subject: New here, Iowa
I was directed to this site/forum by a helpful member at dpreview.com. I run a seed testing lab, or a part of one, doing germination and vigor testing on several different crops. One part of my job that I particularly enjoy is photography - whether for documentation, inclusion in work instructions, amassing images for internal referees between the several labs worldwide within the company, or photographing just for the hell of it.
I have two specific needs that I'd like to take care of by learning more from this forum: photos for tetrazolium testing, which are taken care of fairly well by my current equipment but I'd like to improve upon, and digitizing our seed herbarium. Would also like to be able to, for fun's sake, grab photos of some germination-related fungal pathogens at 10-15x magnification. Of course, occasionally I find something that I just really want to take a picture of, but one can't always plan for things like that.
My current equipment for this consists of a sony a850 dslr, kenko extension tubes, a homemade "bellows" built out of a sigma 70-300 macro case, and an old Minolta Rokkor-X 50mm macro lens that I modified to work at close focus. My workplace has a light table setup with 3 moveable halogen lamps that works fairly well but lacks any sort of fine distance adjustment. I've wanted to get a macro focusing rail to remedy this.
So, that's my story. I don't know enough about this to say more, except that from what I've learned so far I think a good 10x objective would take me a long way toward what I want to do. I just don't know enough about them to be buying one yet.
An idea of what I commonly photograph at work:
A TZ test on sorghum seed - this is about as good a result as I can get from my 50mm Rokkor without stacking:
No measurement bars - this is roughly 4mm vertical dimension
A germinated corn seedling- photos like this make up 90% of my official business and the rokkor works fantastic for this:
Probably 25mm vertical
Will appreciate any advice on where to start! Looking forward to becoming active on the board.