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Sony A7 III sensor testing.

There has been a lot chatter about the A7 mark 3. Both the previous models were excellent low light performers, although there was some discussion in the Astro community they were eating stars. With the introduction of a BSI sensor could this be the camera for you?

Having recently tested the Panasonic S1 I was very interested to see how the A7 III performs, as most people are saying it’s currently a 2 horse race between these two cameras.

Well I happy to say the A7 performs very well, It’s clear that the BSI sensor is much more uniform than previous models and it has significantly less noise.

When comparing it to it’s competition it stacks up very well. It performs very close to the S1, and surprisingly at 5 minutes there is almost nothing in it. The EOS R is the worst of the pack and the A7III is significantly better right across the exposures tested.

I am not sure if the Z6 and the A7III share the same sensor. Getting 100% confirmation on this is very hard, some articles are saying they are the same, while in others the number of raw pixels is slightly different, so maybe they are not. If they are then the 5 minute exposure time could show aggressive NR from Sony. However there have reports that the A7III is not suffering from the star eating problem that previous models had, well not completely it depends on what you read, but it’s better. So you can draw your own conclusions about the Z6 and the A7III sharing the same sensor.

It would be more consistent to conclude the S1 and A7III share the same sensor than the Z6. With many saying this is the case less with only the phase detection pixels removed in the S1. The difference in noise could easily come down to RAW images algorithms, and sensor production variation. It will be interesting to see how the A7RIII and S1R compare.

In my opinion if you currently own Sony gear the upgrade path is a no brainer, the A7III. if you don’t other factors such as cost, lens availability and other camera features are more likely to be a factor if you are leaning to the S1.

It’s also worth noting that ensuring testing temperature is very difficult and this or a future firmware upgrade could easily tip the scales to either the A7III or the S1 or even the Z6. What can be done with a firmware upgrade is amazing. Either way both the A7III and the S1 are excellent long exposure performers and should perform very well.

If you would like to find out more about the Sensor DBclick here.


Sensor DB Upgrade.

It has been a while since the Sensor Database has been upgraded, and it was time with the recent additions of some never sensors.

New features include a better layout with less clutter for comparing models. I have also added pop-up images to allow users to see a true 1:1 view of the sensor noise, rather than a 50% browser rescale. These new features will allow for better comparisons as sensors continue to improve.

To view the new Sensor DB, click here

Canon Consistent with EOS-R & RP

Canon have improved the sensors in the EOS R and RP. The R sensor is based on the same sensor we see in the 5D mark 4, and the RP is based on the same sensor in the 6Dm2 and Canon have managed to squeeze a little more out of both for some good results.

EOS-RP v’s 6D mark II

As you can see the EOS-RP sensor performs much better than the 6Dm2 sensor over the whole range of long exposure times. Canon have possibly continued to improve the manufacturing process or the new DIGIC processing is really working some extra magic. The RP is where I expected the 6Dm2 sensor to be after the fantastic long exposure performance of the original mark I. Better late then never.

EOS-R v’s 5D Mark IV

The EOS-R is also better than the 5D mark IV. It’s not the same jump in sensor improvement as the RP, but it’s still a big improvement of almost 20% less noise at 1 second. Again there is consistent gains over the long exposure testing range.

So it’s a good gain for Canon, but I do feel disappointed again, just like I did when testing the 6D mark II. Canon are making consistent gains with each new model, but the long exposure sensor noise is where the competition was years ago.

Mirrorless, Nikon and Canon

When comparing the R and RP to the Z6 and Z7 based on long exposure base noise alone It would be difficult to recommend Canon, especially if you are not gear biased. The R/RP may do better for extreme long exposures of 5 mins or more, but how these models would compare with dark frames added to remove noise for extreme long exposure I don’t know.

Conclusion:
If you are currently using Canon then the R and RP are a good step up from the 5D mark 4 and 6D mark 2 in regards to sensor noise. If your thinking of upgrading to mirrorless I think both these would perform well and give good results. It’s possibly the most sensible path to go down if you have a lot of EF glass and just want to expand your kit.

The EOS-R has the best long exposure low noise sensor from Canon over 20MP, so if you are after Canon, this is the one to buy. The EOS-RP is also very respectable and not far behind. Will they be the cleanest images money can buy for long exposure?, No I expect not.

If you would like to compare the EOS-R and EOS-RP to more models, or learn more about the sensor database click here.

Again, a big thanks for Alex @Stallards in Hobart for access to these cameras for testing.

Fuji X-T3. Third time lucky?

I’m always in two minds when it comes to the fuji sensors. and like Olympus they seem to be doing noise reduction and low level sensor data manipulation even when it’s disabled in camera. It could be the “grain effects” that make Fuji unique, but it does make it hard to compare their sensors to other bodies.

Having said that the new X-T3 performs much better than the X-T2, even with a few more MP. At 1 and 30 seconds the sensor is much better than it’s predecessor. Noise does build up quicker with longer exposures and at five minutes the results are worse (noise mean), but with less standard deviation.

X-T2 vs X-T3

Compared it to the Nikon Z6, currently the leader for long exposure noise the X-T3 appears to do very well. However as mentioned above this in my mind only shows one thing, that Fuji are seriously processing the RAW data. Keep in mind that the X-T3 is a crop body, where as the Z6 is not.

Thats some serious low noise?

When compared to a crop body like the Nikon D7500 you start to get an idea of what is going on:

Nikon D7500 vs X-T3, whats the story here?

Conclusion:
There is no doubt that the X-T3 is a big improvement on the previous model, the noise has been greatly reduced. However I am really not sure how this camera will perform in a real world low light situation. Either Fuji have a crop sensor that is performing better than any full frame sensor, or they are performing noise reduction. I think the latter is more likely, and how this impacts on some subject matter like stars I guess time will tell. Some real world astrophotography samples would be great to see.

If you would like to compare the X-T3 to more models, or learn more about the sensor database click here.

Again, a big thanks for Alex @Stallards in Hobart for access to the X-T3.

Nikon Z6 & Z7 King of the Hill

Nikon’s last low light monster, the D750 has finally been knocked off the hill. The new Z6 and Z7 with their new BSI sensors have overtaken the D750 to hold positions 1 and 2 for low light performance, at least for exposure times below 30 seconds. Our testing showed at 300 seconds (5 mins) the Z6 and Z7 were significantly worse than the D750, as well as many other models. At what point the sensor introduced the noise is yet undetermined, I expect well above 30 seconds.

So for any application below or at a few minutes the Z6 is going to be better than anything currently available in the market. There is no evidence of star eating, and NR off in camera appears to be “off” unlike some other bodies that add grain or manipulate the RAW data even when set to “NR Off”.

How does the D750 compare to the new Z6 and Z7

The Z7 is still great at 1 second, but starts to fall away when compared to the D750 @ 30 seconds. Keep in mind this is a 46 v’s 24 mega pixel race. So the Z7 performs exceptionally well for its pixel count. At 30 seconds I expect you would be getting wonderfully clean images in low light.

The Z7 seems to perform slightly better at 300 seconds compared to the Z6, which was a bit of a surprise, and it was also out performing the 5DSR and GFX-50S. It was about the same as the A7RmII (I do not have the mIII sample as yet).

If you are looking for exposures in minutes, then I’d maybe consider other bodies. But keep in mind the new Z mount may see some faster glass in the future, which would allow a reduction in ISO, and possibly a more cleaner image, and it is 46MP after all.

Overall it’s a very impressive result, and continues to show that Nikon are working hard with Sony to produce sensors that give exceptional results in low light / long exposure situations.

To compare more models, or see further details, check out the Sensor Database.

A big thanks for Alex @Stallards in Hobart for access to the Z6 and Z7 for testing.

Nikon D7500 Long Exposure Monster.

I’m impressed, the Nikon D7500 is the best crop body I have tested so far for long exposure. It out performs all previous models by quite a margin, taking even the title form the D500. At 1 second it out performs the new Canon 6D Mark II which is full frame, and is is only slightly worse at 30 seconds. Check out the results and compare models here.

 

Playing with the light. ND Filters.

Most good modern DSLR’s have a good amount of Dynamic Range (DR), DR is the measurement from the brightest to the darkest a sensor can capture in one image, beyond this range highlights will be blown and dark shadows will yield no detail. It is normally measured in Exposue Values (EV). A Good sensor will be at least 12, and maybe as high as 16.

But what do you do if the image you are trying to capture has more DR than my sensor can capture? Well there are a number of ways to deal with this, these are the most common:

  • Take multiple exposures to combine into one image, either as a composite merge or a high dynamic range shot (HDR), later models can do HDR in camera.
  • Add additional light to the scene.
  • Use filtering effects to modify the light being exposed.

BPD_1948HDR and adding light are fairly common, but using filters is not very common for night sky photography and Aurora’s. The reason it is not popular is that adding filters reduces the amount of light entering the camera, resulting in either having to use higher ISO settings or longer exposures.

However given the right circumstances using a filter can have great results. I like to use them for shooting Aurora’s provided the Aurora is very bright and it has minimal movement. If the Aurora is bright I don’t need to increase my ISO, and minimal movement like beams in the Aurora will mean I can increase the exposure time a little without blurring any details.

I have found that using a 0.9 (3 stop filter) helps significantly with exposure compensation, balancing out the light Aurora in the sky to darker foregrounds. Not only does it help with the balance and bringing out blacks, but it effectively gives your sensor a 3 stop advantage.

A sensor that can shoot 14 stops of DR is suddenly equivalent to 17.

Suddenly I’m no longer dealing with those horrible black dark areas where the noise hides.

“Someones up late”.

Iron Pot AuroraHad one of those nights last night where I could just not sleep, so I decided to head out and see if I could get a nice shot on a beach where I recalled someone had built a makeshift stick “hut”.

The beach faced north, so I knew if the Aurora Australis was active I’d have to do at least a 200 degree panorama to get it all in. In the end it was only four shots with my 16-35 lens.

I have titled it “Someones up late”.

Shot shows the Iron Pot lighthouse at the mouth of the Derwent River in Storm Bay with Bruny Island to the right (Tasmania). Pictured to the left is a single shot from the same location a little further down the beach.

Oblivious to the lights.

IMG_7875When your out shooting late at night you have a lot of time for thinking during exposures and between shots, especially if your by yourself. I often think of all those people at home, watching TV, or asleep in their beds, oblivious to what is going on around then, and the silent lights that weave across the night sky above them.

I think the mood in this shot sums up how I often think of those people. They are inside, working away or watching some program on TV. Meanwhile outside the lights are dancing in the sky and the stars are shining brightly on a perfectly clear and moonless night.

The picture was taken in Mortimer Bay (Tasmania). The photograph to the right was taken only a stones throw from the boat shed when the Aurora was a little more active.