Using a Telephoto lens to Photograph Flowers

[tropterrarium]

Originally Posted by ronaldhanko

You are correct that a flash is another option - I use a ring flash also in such situations. One does get a lot of odd looks and questions about whether one is a professional and so on.

One has to be very careful with tele flash. In theory, exposure with flash is very short (on the order of 1/1'000-10'000s), so is used to get around a tripod and still have sharp images. The issue with tele flash is that a fairly high flash-power is required. For one, the object is usually further away, second, lenses are not as strong light gatherers. It means, that often the flash is pretty much fully discharged. At full discharge, flash duration is more on the order of 1/200 s. This is also the faster of the flash synchronization times (on older/cheaper cameras it is 1/60s).

What's that all about? The issue is that the longest exposure time one can hand-hold without getting motion blur is 1/focal length in mm (for full frame SLR: for APS the equivalents are actually about 1/3 shorter!). So at 200 mm focal length (on full frame SLR), one is just about at the edge for hand-holding full discharge flash exposures, with longer focal lengths, one still needs a good tripod. That also applies with mixed light situations.

Why is the 1/focal length rule only applicable to full frame SLR? It has to do with the angular deviation that are not going outside the circle of confusion on the sensor. As the total angle of the image is narrower due the smaller sensors on APS-C (and half-frame) cameras, the angular deviations are more pronounced at the same focal length in mm compared to full-frame SLR.

The only options would be the few linear flashes. I once had the OM 280, but the issue is that with shorter shutter speeds, the flash power also declines, something that is not often mentioned in the literature.

[ChasWG]

Hmmmmmm... OK, I'm not argueing with you, mostly because I'm still not entirely sure what you just said. I get a lot of what you said above, but it seems to me that if you spend your time with calculations and theories like that you'll never take any images. Sometimes it just works. Yes knowing what you are doing is great, but trying something new and pushing the limits has it's merits too.

[Connie Star]

Chas and Ron, you both take great photos and are an inspiration.

[tropterrarium]

Chas, my point is quite simple. Flash in often (not always) used as an action stopper and to produce tack-sharp images. With teles-flash, it is not always the case unless it is properly done.

I do subscribe to the idea, that one should thoroughly understand what one is doing, and thereby increases the probability of good images. Additionally, by understanding the principles, one can deliberately deviate from the rules with some idea on what the consequences are. Or one can apply the principles across various imaging systems. I run the gamut from scanning electron microscope to regular light microscopes, SLR, to 4x5" large format. Understanding optical principles helps me to get the most out of each system.

I learned photography in the department of physical chemistry at university, not the art department, so that has certainly colored my perspective. Writing it all out takes time, but I've got that and a bit more internalized, so it's just second nature. Initially, it takes time to understand it, but it reaps benefits down the road. So a very worth-while investment.

I do understand that visually pleasing (art is in the eye of the beholder) images can be made even violating "good" photographic practices. As I bill myself as a scientific photographer, one of the key aspects is tack sharp images. Hand-held tele-flash can lead to images with motion blurr with full-power flash, or ghosting with fill-flash. Yes, I've done both. And both result in instant rejects for the vast majority of publication outlets, therefore, no need to keep those, just toss/delete them.

[Amanda L]

Stunning as always Ron! Thanks for the tip. I need to buy some better lenses for my camera. I have the means to do some extra spending now. I may start the lens collection!

[ronaldhanko]

Good luck, Amanda. Thanks for the note.

[Paul]

That is an excellant 'Picotee' hippeastrum, Ron! Appears to be a pure white with the red picotee -- most I have seen have some reddish blushing marring the pristine white. Yours I would love to have!

[ronaldhanko]

Originally Posted by Paul

That is an excellant 'Picotee' hippeastrum, Ron! Appears to be a pure white with the red picotee -- most I have seen have some reddish blushing marring the pristine white. Yours I would love to have!

It's not actually mine, Paul, but was photographed at Manito City Park in Spokane. It is lovely, though, and I wouldn't mind having it myself.