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Fun With Sony Cameras

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scho

Well-known member
Re: Fun with the Sony A7 and A7r series

Last of the fresh cut flowers from the garden. Rodenstock Grandagon-N 90mm f/6.8 on Cambo Actus with Sony A7R.

 

Annna T

Active member
Re: Fun with the Sony A7 and A7r series

Many thanks Annna T...Always happy to answer (sensible) questions as yours is :)

I tried various EV combinations as the light was getting dimmer...I think I took around 40 images in all!
Wow ! 40 images ! That's even more than myself (and I'm already flooded with same shots of everything). I find it hard to get more disciplined and to only keep the best ones. How do you manage so many files ? That is a lot of work to sort it all out and then to store the best.

I first started out with a more sensible choice of aperture/shutter speed with a faster ISO and then experimented seeing just how slow I could get the shutter speed down to by simply hand balancing it on top of the fence.
On inspection at home I decided to go with the smooth water image (4 seconds was the maximum I could hold it still).
Thanks for your explanations. I see the challenge. Holding the A7r perfectly still for 4 sec. is quite a performance, even leaning on a barrier.

I was unaware that you loose DR at 50 ISO + Surprised that the optimal performance for the A7R sensor is at 200 ISO (I must admit pixel peeping that’s not my experience in daylight). Although I was aware that thermal noise starts coming into play at low EV’s. (I live and learn - Thanks).
DPreview has shown that in its review of the A7r. 50 ISO, like on many other cameras is a "fake ISO" : the camera overexpose and boost the shadows afterward. This results in a loss of DR in the highlights. They have issued a graph illustrating that here (look for the last graph at the end of the page).

I got a little unsure about 200 ISO offering better performance than ISO 100. I used to shoot at ISO100, then read about the 200 ISO being better and switched to ISO200. So I made a little more research and nothing confirms that : ISO100 offers also better DR and lower noise (although the difference is subtile). May be those who propagated the idea that it is better to shoot at ISO200 were taking the higher resolution of the sensor in consideration and pushing for faster speeds. Personnally, not having very steady hands, I tend to prefer ISO200 rather than ISO100.

Here is what I found concerning the variation of DR and noise depending on the ISO used :

DXO data

Sensorgen

This last series of graphs is interesting : contrary to what DPreview states they indicate sligthly better results with ISO50 than ISO100. But the difference is sot subtle as to be negligible. In theory, DPreview should be right, but what Sensorgen found out seems to match what you say.

To be honest I'm not so hung up about "Noise" as some others are here...In my Leica M and R days I used to deliberately enhance the acutance of film grain (Tri-X and TMax 3200) by developing in Agfa Rodinal and making small prints.
I like a clean digital look. May be because I never had a darkroom. I shot several years with film, but used to scan my negs or slides. Digital cameras were a real relief :) and they made the learning of photography technique so much easier.

Thanks for all the explanations you are always generously offering.

BTW : your costal pictures of England are always so beautiful that they make me wish to pay a visit there once.
 

Barry Haines

Active member
Re: Fun with the Sony A7 and A7r series


40 images ! That's even more than myself (and I'm already flooded with same shots of everything). I find it hard to get more disciplined and to only keep the best ones. How do you manage so many files ? That is a lot of work to sort it all out and then to store the best.


Hi Annna, to be honest 40 images is generally on the low side for me when I see something that I want to capture (I'm sure I'm not alone here)...I pretty well machine gun a subject to death, scan through the JPEG's quickly as they display faster than what RAW does on my ancient PC when I get home, then just grab the corresponding best RAW image and work on that...Needless to say I am now on my second A7R.
I just buy a couple of 2TB Western Digital passports each year and save the good with the bad (Shameless to say that is mostly everything)...I really haven't the patience to sort them all out nor the inclination...Storage is so cheap these days and time is much more important to me (I can still see to my parents and have a life at the end of the day).



Thanks for your explanations. I see the challenge. Holding the A7r perfectly still for 4 sec. is quite a performance, even leaning on a barrier.


As you say it was the challenge that interested me at the taking stage.


DPreview has shown that in its review of the A7r. 50 ISO, like on many other cameras is a "fake ISO" : the camera overexpose and boost the shadows afterward. This results in a loss of DR in the highlights. They have issued a graph illustrating that here (look for the last graph at the end of the page).

I got a little unsure about 200 ISO offering better performance than ISO 100. I used to shoot at ISO100, then read about the 200 ISO being better and switched to ISO200. So I made a little more research and nothing confirms that : ISO100 offers also better DR and lower noise (although the difference is subtile). May be those who propagated the idea that it is better to shoot at ISO200 were taking the higher resolution of the sensor in consideration and pushing for faster speeds. Personnally, not having very steady hands, I tend to prefer ISO200 rather than ISO100.

Here is what I found concerning the variation of DR and noise depending on the ISO used :

DXO data

Sensorgen

This last series of graphs is interesting : contrary to what DPreview states they indicate sligthly better results with ISO50 than ISO100. But the difference is sot subtle as to be negligible. In theory, DPreview should be right, but what Sensorgen found out seems to match what you say.


Thank you so much for that Annna...I tried to do a search for that information (DR on 50 ISO & 200 ISO optimal) without any joy...I will have a look this evening, now that you have pointed me in the right direction...much appreciated.



I like a clean digital look. May be because I never had a darkroom. I shot several years with film, but used to scan my negs or slides. Digital cameras were a real relief :) and they made the learning of photography technique so much easier.

Thanks for all the explanations you are always generously offering.

BTW : your costal pictures of England are always so beautiful that they make me wish to pay a visit there once.


Thank you again Annna, I think you would like Cornwall, so many interesting things to photograph (not cities though).
Please don't get me wrong regarding grain in film...I encouraged the enhancement of it in smaller formats like 35mm film but when I was shooting 10x8 or 14x11 inch sheet film I did everything that was possible on this earth to extinguish it!...In fact I was completely obsessed with it's removal/disguise ie. FP4+, TMax 100 and Tri-X developed in my own staining Pyro developer, contact printed onto a slow silver chloride paper (Kodak Azo, which I used to get from Michael A Smith) developed in my own Amidol paper developer...That will still give you a much "CLEANER" looking (Contact size) print than anything digital even today IMHO. I realize noise is different from grain but it just doesn't bother me all that much...If you like the clean digital look you should go with that...You are most welcome Annna, always happy to share...I do ramble on a bit so apologies to others here...Cheers Barry
 
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Barry Haines

Active member
Re: Fun with the Sony A7 and A7r series

DPreview has shown that in its review of the A7r. 50 ISO, like on many other cameras is a "fake ISO" : the camera overexpose and boost the shadows afterward. This results in a loss of DR in the highlights. They have issued a graph illustrating that here (look for the last graph at the end of the page).

I got a little unsure about 200 ISO offering better performance than ISO 100. I used to shoot at ISO100, then read about the 200 ISO being better and switched to ISO200. So I made a little more research and nothing confirms that : ISO100 offers also better DR and lower noise (although the difference is subtile). May be those who propagated the idea that it is better to shoot at ISO200 were taking the higher resolution of the sensor in consideration and pushing for faster speeds. Personnally, not having very steady hands, I tend to prefer ISO200 rather than ISO100.

Here is what I found concerning the variation of DR and noise depending on the ISO used :

DXO data

Sensorgen

This last series of graphs is interesting : contrary to what DPreview states they indicate sligthly better results with ISO50 than ISO100. But the difference is sot subtle as to be negligible. In theory, DPreview should be right, but what Sensorgen found out seems to match what you say.
That was an interesting read Annna (Thank you once again :) )...I'm not sure I am any the wiser, perhaps I should do a few tests of my own...I made a few changes to my normal camera settings and will see if I can see any real world difference at the lower ISO's, especially the highlights.

I have included the links for others to see below.

Sensorgen..... Sensorgen.info data for Sony A7R

Dpreview.... Sony Alpha 7R Review: Digital Photography Review
Sony Alpha 7R Review: Digital Photography Review

One of the problems is that Sensorgen don't tell you what the camera settings were that they used and that WOULD affect the results...Their results are totally different (@ 50 ISO) from DPreview's as you say.
Cheers Barry
 

Barry Haines

Active member
Re: Fun with the Sony A7 and A7r series

Three adults tragically died at the weekend at Mawgan Porth beach
(Witnesses have reported that they were trying to save young surfers in difficulty).



 

Annna T

Active member
Re: Fun with the Sony A7 and A7r series

That was an interesting read Annna (Thank you once again :) )...I'm not sure I am any the wiser, perhaps I should do a few tests of my own...I made a few changes to my normal camera settings and will see if I can see any real world difference at the lower ISO's, especially the highlights.

I have included the links for others to see below.

Sensorgen..... Sensorgen.info data for Sony A7R

Dpreview.... Sony Alpha 7R Review: Digital Photography Review
Sony Alpha 7R Review: Digital Photography Review

One of the problems is that Sensorgen don't tell you what the camera settings were that they used and that WOULD affect the results...Their results are totally different (@ 50 ISO) from DPreview's as you say.
Cheers Barry
They are using both DXOmark data and statistical data which they compute using Rawdigger. They extract the data from the raw files using converters like DCRAW, aka they try to get the rawest data possible (not what you get from commercial converters like LR, C1, or DXO, where a ), their only goal is to analyse the pure sensor performance, before any settings are applied. When you open an image in Rawdigger, you get a statistical analysis and a graph instead of a converted picture : it isn't for the faint of heart :)

There are some explanations there and links to the results of other cameras/sensors: Sensorgen - digital camera sensor data

There is another website explaining sensor performance : Clarkvision I'm sure it had a page allowing you to compare the performances of different cameras depending on the ISO used, but I couldn't find that page again.
 

Barry Haines

Active member
Re: Fun with the Sony A7 and A7r series

They are using both DXOmark data and statistical data which they compute using Rawdigger. They extract the data from the raw files using converters like DCRAW, aka they try to get the rawest data possible (not what you get from commercial converters like LR, C1, or DXO, where a ), their only goal is to analyse the pure sensor performance, before any settings are applied. When you open an image in Rawdigger, you get a statistical analysis and a graph instead of a converted picture : it isn't for the faint of heart :)

There are some explanations there and links to the results of other cameras/sensors: Sensorgen - digital camera sensor data

There is another website explaining sensor performance : Clarkvision I'm sure it had a page allowing you to compare the performances of different cameras depending on the ISO used, but I couldn't find that page again.
Thanks again Annna...You have obviously spent much, much more time than me delving into all of this. :salute:
I think Sensorgen's calculations as you say are from the physical raw RAW information gathered from all the many different cameras that they have tested to date with DXO.
This link is for the calculations if anybody is interested..I will admit it's all a bit beyond me :D http://www.sensorgen.info/Calculations.html

When I read on DPreview (A7 model and to some extent the A7R) that just switching off the high ISO noise reduction physically meant that the actual RAW file itself was still being subjected to noise reduction...I begin to question what is a normal RAW file!...That is why I said I will try altering my cameras settings (A simple test that we can all do). I now wonder which camera settings did Sensorgen actually use to determine their results that they have presented to us?

Sony Alpha 7 Review: Digital Photography Review
See under "Posterization"
Turning the cameras' 'High ISO NR' to 'Off' improves matters (at all ISOs), because the standard processing appears to be supressing noise to such a degree that you lose the 'dithering' effect that noise usually brings to tonal transitions. The downside is that you have to put up pretty noisy high ISO images (noise reduction, in both JPEG and Raw is still being applied in the 'Off' setting).

I could see a noticeable amount of "extra" noise at 200 ISO compared to 50 ISO (ACR NR off) on the ACR noise comparison chart...I wonder if 200 ISO is really the optimal ISO to go for if you are using ACR which many of us are.
Sony Alpha 7R Review: Digital Photography Review
 

Georg Baumann

Subscriber Member
Re: Fun with the Sony A7 and A7r series

The Island Ailsa Craig can be seen in the background of the fog horn. It is the only place in Scotland where the material for curling stones comes from. Red, Green and common Ailsa granite are used for poslishing. The granit is more dense than usual, but still has superb polishing qualitites.

One company only is allowed to harvest the granite, and only from rocks that are to be fund, no mining operation or dynamite allowed as thisw is a nature reserve for birds.

There is one more place where such stone can be found, I believe it is in Wales.

http://www.kaysofscotland.co.uk/about-ailsacraig.php
 

scho

Well-known member
Re: Fun with the Sony A7 and A7r series

Taughannock Falls on the west shore of Cayuga Lake. Sony A7R, Cambo Actus, Rodenstock Grandagon-N 90mm f/6.8. Two shots stitched.



Lower falls at the bottom of the gorge just above lake level. A 9 shot stitch using AutoPanoPro3. Should have used a wider focal length for this scene, but 90 is all I had in my bag at the time.



Hemlock roots on the gorge walls. Single shot.

 
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biglouis

Well-known member
Re: Fun with the Sony A7 and A7r series

Last Fruit - orchard, Cressing Temple Barns, Essex, UK

Sony A7r+CV21/1.8

 

pegelli

Well-known member
Re: Fun With Sony _____

Here's some from the Isabella Plantation inside Richmond park:

Entrance


Green


Blackbird in B&W


Fall colour


Larch


Outside of the plantation, towards the lakes: Surveying the hunting lodge


1, 2, 4 and 5: NEX6 + Summaron M 35/2.8
3 and 6: A900 + Min 200/2.8 HS G + Sony APO 1.4x converter
 
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