Caesalpinnia Pulcherrima - Sigma 105 macro

I bought a Sigma 105 macro to go with my *ist D back in October after much reading here and elsewhere. I've really enjoyed trying to capture the detail of some of the flowers growing in and around our garden. Below is a shot of a Caesalpinnia Pulcherrima flower from our front garden. The shot was taken in a home made light box made from an old cardboard carton with tracing paper windows and lit by a couple of ordinary 40w reading lamps.




Any comments or advice appreciated.

Steve

Exif Data:
Exposure 2.0s at f/27
ISO: 200
Manual white balance
Pentax *ist D and Sigma 105
Edited in CS2

Hi Steve,
Welcome here and what a beautyful flowers you can choose from,growing in your garden. A heaven made for macro, i reckon
I love the way you composed this flower in the frame. Sharpness is there were it should be. I wonder how this picture should look if you converted it to a very highkey monochrome picture. I could see that version hanging above my couch in a nice frame. But hey......i am a sucker for monochrome fine art prints. Can't help that

regards,
Martin

Nice shot but looks a bit soft to me.

Did you try taking some at f11 or f16? If yes, you might find that the in-focus portion is sharper at the expense of DOF, but that's no big deal.

I think we'd be hard pushed to say whether it was critically sharp at this size, but f/27 is a very small aperture and Mannesty's almost certainly right to suggest a wider one. Have a look at the MTF chart here: http://www.photozone.de/8Reviews/lenses/sigma_105_28/index.htm , you'll see the resolution of the lens is much poorer by f/22.

I find f/8 to be sharpest with my Sigma 105mm, but then depth of field is going to be a lot less than at f/27. Without knowing how large (or small) the flower is it would be hard to say whether DoF at the larger apertures would be too detrimental.

But it's a nice study, I like it.

Dan

Thanks for your comments Martin. I will have to experiment in photoshop with converting to monochrome. Not something that I have tried so will have to play around and see what I can do. Any suggestions of where I might find advice on converting photos to monochrome?

Daniel and Peter, thanks for your comments. I'd have to look back at the other photos that I took but I know that I was having trouble getting everything in focus. The stamen are about 5cm long and to get the pollen on the ends and the petals all in focus wasn't easy. I would estimate that at the angle that I took the flower at the distance from front to back is about 6cm. I'll have to have another go using a bigger aperture and try to vary the focusing slightly to see if I can get it sharp and in focus.

Cheers,

Steve

I'd say it was probably impossible. The pollen is definitely out of focus with this one, but I don't think it looks bad at all.

Dan

Interesting charts, Dan. I see that the 77mm Ltd is significantly sharper than the FA 100mm macro, which is sharper than the best Canon 100mm macro, which is sharper than this Sigma.

The 31mm is even sharper than the 77mm, and the 43mm Ltd is sharpest of all.

The new micro Nikkor isn't bad, but it can't match the Ltds.

Sigmas represent good value for money, but tell me, why do people buy Canniks?

G

Hi Steve,

Welcome to the forum, you couldn't be anywhere better to improve your photography, it will be interesting also to see images froma different part of the world.

Now, re the above ? following this link, Josh got me going on mono conversion, you can't go wrong with his method, good luck and post them up.
https://www.pentaxuser.com/forum/viewtopic.php?t=3838&start=0
ps- I agree with Martin reckon your image wd look great in mono

cheers
Lilly

You could try taking 2 or more photos, each focusing on a different part of the flower, then layer them in PhotoShop rubbing out parts of each layer that are out of focus, leaving only the 'sharp' parts.





This is an example of what I mean, both ends of the door hook are in focus, but in the original 2 pictures, only one end was in focus in each picture.

Should be quite easy to do on a static subject like a flower with a plain background ?

Because they're deluded, or daft, or both.

Although, to be fair, the Canon tests were, I think, done on the 8mp 350D, so direct comparison with the K10D isn't quite as straightforward as it would be nice to think. The higher resolution of the sensor may well have a bearing on the results.

Dan

Yeah they cant be compared between systems at all really - the max score on the 350D was like 2050 or 2150, on the K10d its 2350
But it still lets you know that the 77 on a K10D completely owns the 100mm on a canon heh