a6400 to a7RIV upgrade for Birding?

[Metaquatic]

I bet you guys are tired of the "Should I upgrade?" questions.  Well tough.  At least I know what I want.  Maybe you can help me decide.

Background:  When I got into birding I chose a camera (a6300) over binoculars because the optical (cropping) zoom and image capture go a long way for bird ID and documentation.  Over time I developed a portfolio of wildlife species that has become my trophy room.  I get asked to do presentations about birds and wildlife and have two pics published where I get to show my photos.  At some point I decided my pictures were horrible!  With the help of a few real photographers I got off auto mode, bought Lightroom, and started worrying about composition and light.  The problem has mostly been after cropping photos the pictures are too grainy for my pixel peeping taste.

My current gear:  a6400, Sony FE 100-400 GM, Sony FE 200-600 G, 2X TC

WHAT I WANT is an 8x10 of the best quality pic I can get of a 4" bird 50' away in low light.  It is assumed that there will be a lot of cropping.  Will an upgrade the a7RIV be the best choice for that endeavor? 

I appreciate comments from anyone who has upgraded from an APS-C to the a7RIV.

Thanks for taking the time to read this!

[Chrissie]

I have not done that conversion, but can give you some things to consider nevertheless. Let's do some math:

An object of 4" at a distance of 50 feet (=600 inches) translates into an object-angle of Arctan(4 / 600) = 0.382° . That's pretty small.

The sel100400gm at the tele end covers an angle of view of 6°10', while the sel200600 at the tele end covers an angle of view of 4°10'.

Let's continue with the sel200600:

Your object covers only around 1/11  (0.382° / 4.166°)  of the angle which the lens sees.

For the 6400 @24MP (6000x4000) that's 6000 / 11 = 545 Pixels. You get the benefit of the APS-C crop factor of 1.5 though and arrive at 545 x1.5 = 818 Pixels covered (in one dimension).

For the 7rm4 @61MP (9504x6336) that's 9504 / 11 = 864 Pixels. No crop-factor though, so not much gained in terms of pixels covered.

In my opinion, that's not the way to go.

Those tele lenses are not very fast (6.3 at the tele end). If you add the 2xTC, you'll loose another full stop and arrive @12.6. Then you're shooting in low light conditions. So my educated guess is, that it's the high ISO that's making your images grainy. Adding more pixels to throw away will not help in that situation, imo.

Have you considered the A73, which is considered a Low Light Performer by some?

Quote

The A7 III delivers its best image quality at its base sensitivity of ISO 50, where it achieves very good color depth of 25 bits and a dynamic range of 14.7 EV. Both of those measurements are very good, but the highlight is the low-light score, which at 3730 ISO is the highest of any full-frame 35mm sensor we’ve tested.

 

P.S.: rumor has it, that there may be an upcoming A7 IV  in 2020.

 

Edited June 18, 2020 by Chrissie

[AntDX316]

On 6/17/2020 at 10:05 PM, Metaquatic said:

I bet you guys are tired of the "Should I upgrade?" questions.  Well tough.  At least I know what I want.  Maybe you can help me decide.

Background:  When I got into birding I chose a camera (a6300) over binoculars because the optical (cropping) zoom and image capture go a long way for bird ID and documentation.  Over time I developed a portfolio of wildlife species that has become my trophy room.  I get asked to do presentations about birds and wildlife and have two pics published where I get to show my photos.  At some point I decided my pictures were horrible!  With the help of a few real photographers I got off auto mode, bought Lightroom, and started worrying about composition and light.  The problem has mostly been after cropping photos the pictures are too grainy for my pixel peeping taste.

My current gear:  a6400, Sony FE 100-400 GM, Sony FE 200-600 G, 2X TC

WHAT I WANT is an 8x10 of the best quality pic I can get of a 4" bird 50' away in low light.  It is assumed that there will be a lot of cropping.  Will an upgrade the a7RIV be the best choice for that endeavor? 

I appreciate comments from anyone who has upgraded from an APS-C to the a7RIV.

Thanks for taking the time to read this!

If the bird isn't moving.. A7R4 is the ultimate quality for Sony cameras at the moment.  Some people had good luck shooting things in flight and even a flying dragonfly but I haven't.  I have a 200-600mm 2x TC too with Olympus EE-1 but haven't had luck w/ good bird shots in flight.  I didn't really get the setup for only that reason though.  I like to see things from very far away.

Imo, having a 100-400 GM and a 200-600 G with 2x TC on an A6400 is pretty crazy to Not have at least an A73, A7R3, A9 1/2, or an A7R4.

Edited July 5, 2020 by AntDX316