A case for Micro Four Thirds in Astrophotography (Reference: Current 16mp and 20mp MFT sensors)
Resolution is something that most photographers like, and for AP, it really helps in the end if you have room to play while maintaining a certain level of quality in your work flow. AP, as I’ve learned, is an expensive pursuit. When one tries to match flawless full frame optics with full frame sensors, the sticker shock is a gut check. The idea of full frame talk has always seemed, well, misunderstood to me. For AP, regardless of full frame, APS-C, or MFT, I believe it’s better to think in terms of Field of View. If you do this, and tune out the format loyalist pundits, you will not only save a mortgage worth of money, you may in fact find an unmatched quality point. I love my A7S, mostly due to it’s live view capabilities, but if I were to start all over (or advise someone) with AP investments, I would procure my optics based off Micro Four Thirds FOV. I’ve been evaluating Micro Four Thirds since they were released into the market. For general photography, there is an element of out of focus areas and depth of field aspects that MFT differs from FF. These points are valid for general use. For AP, these points are void and you are left with a single difference, FOV. For the newer models, there are always going to be slight response/performance differences between every camera model. The slight variations might be a deal breaker for some, but for all of my MFT/APS-C/FF cameras, in the end, these differences are relatively unnoticeable and therefore I exclude these small differences as it relates to the end finished product. Some will say that MFT is just a crop. This is true, and only true, if the sensors are of the exact same characteristics. Case in point : my 16mp MFT Olympus’s are completely different than my 12mp FF A7S. The quality of a MFT FOV cropped A7S file is nowhere even close to the quality of a native MFT Olympus 16mp capture. Not only is the quality different, the obvious difference in resolution is apparent. Even a MFT crop of, for instance, a A6000 24MP sensor is not the same as an Olympus 16mp MFT native capture. It’s more likely that the statement “A MFT is simply a FF crop” is NOT true than to find that it is true. Think of it this way, what would it take for the statement “A MFT is simply a crop of a FF” to be true as it relates to my Olympus 16mp sensor? Hold on tight – it would require a 88.5 mp FF sensor. How many of those do you see available on the market? This should put the MFT 16mp sensors into a new perspective for you.
Back to optics. In most circumstances, in order to get a completely flat full frame, it requires a lot of $. As an example, completely flat optics in the 500mm and above range, the price would be IMO $2 minimum and probably $3K on average, and can go way way up from there. Even then, It will be a challenge to calibrate your high performance gear to actually perform perfect on a full frame.
Why all hassle? If you want a quality output, match your optics up to a MFT FOV and give it a try. In doing so, you will see that some of the benefits will include:
- You will be able to use less costly optics, while obtaining results that will match, or in most cases beat, premium full frame performing optics. You still need good optics but the idea here is, as an example : If you need a 400mm FOV for imaging, research a 200mm lens that, although may show imperfections on a full frame, provides a quality field for a MFT camera. Not only will you have the resolution to support it, you will NOT be able to tell the difference in the end unless you’re a professional pixel peeping expert. Might you see a small difference when evaluating a single sub? Maybe, maybe not. Stack at least 20 frames and I would say that the ability to distinguish would be extremely difficult. This one example alone will save you thousands of dollars in your AP investment. The pundits will say this is not true and mathematically they will probably provide an equation that will support the claim. From a visual standpoint, and as an actual user (and have been for years in general), I can tell you that, if there is any difference, it is minimal – so minimal that it’s almost unnoticeable in the end.
- This will eliminate the need to crop any of your image, aside from the small stacked edges. I see many folks image with less than perfect optics and end up within the MFT FOV with their FF bodies anyway. Why not just image with MFT? Cut’s out a lot of work and frustration.
- You will not have any vignette issues.
- The camera bodies are light and small
- MFT are extremely cheap relative to full frame bodies
- Perspective – a Olympus 16MP MFT file is roughly 13 megabytes in size. A A6000 24MP aps-c file is 26MB on average. If I crop the A6000 file to equal the FOV of the Olympus, I would be left with a 10MP file – again, no where even close to the 16MP resolution of the Olympus 16mp MFT native file.
To back up what I say, I’ve got three – two hour stacks of IC342. One stack is made with the Olympus M10 with a cheap 920mm F4 Newtonian (with Paracorr) and one two-hour stack made with a A7S with the Edge HD8. Lastly I’ve got a two hour stack made with the A6000/920mm F4 newt. The highest resolution end result, and the highest quality file with less AP issues, is the Oly M10 stack. If anyone is interested, let me know and I’ll send you the link for your review.
FOV with Oly/Newt outlined above : 1840mm
FOV with A7S/EdgeD8 outlined above: 2030mm
FOV with A6000/Newt outlined above : 1380mm
Anyway, my wife is on vacation and I’ve got more time on my hands than what Is good for me. Thought I would share my thoughts on this issue.