[csa]

I've been a big fan of my Tamron F 1.4X Pz-AF TC. Today I did a little comparison with/without it, using my Sigma 300 F4.

#1 With TC (no PP, except resizing)

#2 Without TC, no PP, except resizing)

#3 Without TC, Cropping, and resizing)

So, what do you think of the results? I'm kind of going with the lens alone, without the TC.

Attached Images

View Picture EXIF

File Date

 

View Picture EXIF

File Date

 

View Picture EXIF

File Date

 

[BigMackCam]

Interesting, Carol. I've often wondered this myself, shooting the DA*60-250 + HD DA 1.4x converter.

In your specific situation, I believe you're shooting JPEG straight out of the camera, right? One of the things I think I notice with your non-TC cropped shot is that the sharpening effects are slightly amplified, as you would expect by enlarging a smaller area of the image to the same scale. That gives the illusion of a sharper image than the uncropped TC image, but I wonder if it's really any sharper. I suspect the detail in the TC image might be a hair better, just not as visibly sharp.

I also think shooting with the TC might have some benefits at higher ISO settings, as the higher pixel density for the same subject magnification should result in slightly less intrusive noise.

If you're shooting JPEG as I think you are, I'd be tempted to try increasing the in-camera sharpening on your TC shots, and see how those compare with the non-TC shots using your normal sharpening level. I think it's worth experimenting a little.

Aside from the above, all three shots look great to me, so I don't think you could make a bad choice

Very impressed with the shots you're getting from that Sigma. Good lens + good technique = great results

[c.a.m]

The first and third images appear similar and comparable to me.

Were the two birds at the same subject distance from your camera? It might be useful to indicate the extent of the resizing.

I note that the ISO is 1600 in the first image and 1000 in the second image. On my K-3 II, I notice a higher noise level at ISO 1600 than at 1000. The quality of these test images might be affected by noise, but it's not immediately obvious in the displayed images here.

Incidentally, we see these two species regularly at our backyard feeder. The chickadees are almost feeding from my hand, but the nuthatch is still wary.

- Craig

[csa]

Hi Mike, yes I shoot JPEG. I'll do a little experimenting with the in-camera sharpening for the TC shots and see what happens.

Thanks!

[csa]

Yes, the two birds were the same distance from the camera, just at a different area of the branch.

They were all resized to 640x426. I've been using the ISO in auto, with 3200 top limit.

Craig, try some peanut butter with the Chickadees; they indeed will eat from your fingers! Yes, the little Nuthatches are more timid, and won't come close to you, like the Chickadees. In the mornings when I bring the feeders out, and refresh the peanut butter, I'm mobbed by the Chickadees!

[UncleVanya]

There have been other comparisons made and depending on the TC and lens combo it has been shown that you can get increased resolution from a TC but that's not a given with all combinations.

It is also important to recall that the TC aids in framing and seeing your subject depending on the subject...

[zzeitg]

I have zero experience with Sigma 300mm f/4, but I suppose that Sigma 300mm f/2.8 with 1.4x TC would lead to better results.


That being said, I must add that my experience with DA*300 f/4 & 1.4x TC (Pentax) has been mostly positive so far. And for me the longer reach is a must, at least as long as I try to shoot tiny birds of this size.

[normhead]

Yes, the little Nuthatches are more timid, and won't come close to you, like the Chickadees.

I used to to have a little Nuthatch who'd sit on the bill of my baseball hat while I put chopped nuts in one of my hand made feeders. There are many Nuthatches in the park that will land on your hand. They just have to get used to you. The Blue Jays come and snarf down the chopped nuts, the little guy knows he has to get there while I'm too close to the Blue Jays for them to come, and before I leave when I'm finished with the feeders. He's pretty aggressive when there are chopped nuts on the line.



hmmm.. 280mm, thats the DA*200 with the 1.4 on it.

[mikeSF]

I do not understand the field of views you have chosen here. Also can you detail how they are sized in comparison to each other? I would think the proper way to test a TC is by comparing its resulting FOV against the solo lens that has been cropped to similarly fill the frame of the lens w/TC.

Also, you should remove the in-camera sharpening before a proper comparison could be made.

[csa]

"I do not understand the field of views you have chosen here. Also can you detail how they are sized in comparison to each other?"

I'm not understanding the field of views? Also, detailing how they are sized in comparison to each other? Not sure what this means.

Mike, I stood in exactly the same spot, took the photos on the same old stump, and resized them exactly the same. I'll let it go at that, and again, sorry for my lack of expertise.

[mikeSF]

"I do not understand the field of views you have chosen here. Also can you detail how they are sized in comparison to each other?"

I'm not understanding the field of views? Also, detailing how they are sized in comparison to each other? Not sure what this means.

Mike, I stood in exactly the same spot, took the photos on the same old stump, and resized them exactly the same. I'll let it go at that, and again, sorry for my lack of expertise.

If you've resized them all the same, ie to have a manageable size for posting, then all this comparison really provides is a comparative magnification between the three configurations.
I would suggest that to draw a conclusion as to whether the image quality of a TC is worth using or not, you would need to crop the non-TC image and resize it to approximate the field of view of the image with the TC attached. This would simulate the real world application of using the TC, since few people would be using a TC for a purpose other than needing to fill more of the frame than the solo lens can provide.

I don't have time to explain better, but hopefully that makes some sense.

[BigMackCam]

I would suggest that to draw a conclusion as to whether the image quality of a TC is worth using or not, you would need to crop the non-TC image and resize it to approximate the field of view of the image with the TC attached.

Unless I'm mistaken, Mike, I think that's what Carol did... so the first shot is with TC, the third shot is without TC and cropped to the same magnification (therefore mimicking the effect of the TC), with both images exported to the same physical dimensions. It's just that the birds in both shots were in slightly different positions on the same tree.

Carol, it might be worth setting up a test subject - something with lots of fine detail - at distance, and taking some with/without TC shots of that. Having exactly the same subject in a consistent position for the shots would help you to get the cropping proportions for the non-TC images just right, and that would allow a slightly more accurate comparison. You could even take the opportunity to do some higher ISO shots and test my theory about less-intrusive noise from higher pixel density. Just thinking out loud, here

[csa]

Unless I'm mistaken, Mike, I think that's what Carol did... so the first shot is with TC, the third shot is without TC and cropped to the same magnification (therefore mimicking the effect of the TC), with both images exported to the same physical dimensions. It's just that the birds in both shots were in slightly different positions on the same tree.

Exactly what I did. Yes, it was not a good test, as I couldn't "will" the birds to land in the exact spot, but #1 and #3 were my "comparisons".

Mike, I'll try testing as you suggested; but it will have to wait for warmer weather, when I did this quick venture it was below zero.

Looking forward to doing a test like Mike suggested, and with the help provided here, I'll learn much more about the lens and the TC!

[normhead]

I did an article on this a while ago... TC's may not improve every image, but they improve some images.
Understanding folks saying a TC doesn't ad more detail. - PentaxForums.com

[mikeSF]

Thanks for the clarification. I certainly did not mean to add any extra homework this is great