Olympus E-P5 digital teleconverter; how does it work.

bikerhiker

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I'm starting to use the digital teleconverter on my E-P5; mainly with my 35-100 f/2.8 so it gives me a 70-200 f/2.8 equivalent I think at 2x and I set it up so I can access it with a press of a function button. I like it the flexibility of it when shooting sports, because I can quickly switch between 1x and 2x. How does this work in regards to image quality and what level of pixels am I looking at quantity wise? 16MP or less?

Any help on this would be greatly appreciated!
 

zensu

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I'm no expert but from what I've read here and on other forums the digital teleconverter on the E-P5 takes the very center 4mp of the sensor and using mathematical formulas and interpolates that up to 16mp. From most of what I've read this is a much better image than simply cropping the center in post processing. I'm pleased with the way my E-P5 interpolates looks compared to what post processing cropping does.
 

bikerhiker

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I'm no expert but from what I've read here and on other forums the digital teleconverter on the E-P5 takes the very center 4mp of the sensor and using mathematical formulas and interpolates that up to 16mp. From most of what I've read this is a much better image than simply cropping the center in post processing. I'm pleased with the way my E-P5 interpolates looks compared to what post processing cropping does.
Thanks Zensu for the quick explanation. I'm also pleased with the way my E-P5 interpolates as well.
 

davidzvi

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Well I for one can tell you it seems to work better than any "Digital zoom" I've ever used in the past.

Not bad for an E-P5, 14mm Pan with the digital converter / f2.5 / 1/25 / ISO 3200 - JPeg right out of the camera.

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Replytoken

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Doesn't this mode turn the center 4MP that Bobby mentioned above from a 1x1 to 4x4 pixel arrays?

--Ken
 

Klorenzo

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I think it just crops the central area, giving you an 8 mega-pixel file. The exposure is measured on the cropped area only. There should no resampling/upscaling involved.
 

sgreszcz

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I'm still not clear if the olympus re-samples or does a straight 2x crop like panasonic ETC mode?
 

zensu

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I'm still not clear if the olympus re-samples or does a straight 2x crop like panasonic ETC mode?
I can't say for sure but everything I've read says it resamples for the JPG so it's the same size as an uncropped JPG. As others have said the Raw is un-resampled and does not show the cropping.
 

Markb

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My frames shot with the teleconverter have the same pixel dimensions and approximate file size as those shot without it. That suggests resampling and upscaling to me but I could be wrong :confused:
 

D7k1

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IF you shoot video this is one very cool tool. It along with IBIS makes this a great video camera as long as you don't pan fast. If Oly would up grade their codec or when the have 4K, I would find the EP5 the perfect camera. I'd sell my other stuff and go 2 EP6/7/8 whatever and be happy.
 

Replytoken

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I'm still not clear if the olympus re-samples or does a straight 2x crop like panasonic ETC mode?
I thought that Olympus resampled and that Panasonic's ETC in video was not downsampled, but rather 1:1 with no resampling.

--Ken
 

sgreszcz

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IF you shoot video this is one very cool tool. It along with IBIS makes this a great video camera as long as you don't pan fast. If Oly would up grade their codec or when the have 4K, I would find the EP5 the perfect camera. I'd sell my other stuff and go 2 EP6/7/8 whatever and be happy.
I just swapped my e-m5/e-pm2 for two refurbished e-p5 bodies in the olympus sale. I love them and don't feel like I'll miss the old cameras. The vf-4 is awesome for manual focus am shooting outdoors!

The controls are amazing, although sometimes I still forget to switch the ISO/wb back to aperture/shutter.

I would definitely love to see an upgraded e-Px with 4k and better video features like we see in panasonic...
 

MajorMagee

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Yes, the E-P5 resamples the center pixels 4:1 and projects them back onto 4608 x 3564. I just did a keyboard test in pretty dim lighting (1/6 sec, f/5.6, ISO 1600), and the results are pretty much identical to scaling 200% in PhotoShop right down to the ISO noise. With no apparent loss of IQ using the digital Teleconverter, it seems to be a reasonable way to compose your enlargements live versus cropping in post process.

I always use spot metering so for me there was no difference in the exposure between the two methods.
 

sgreszcz

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Yes, the E-P5 resamples the center pixels 4:1 and projects them back onto 4608 x 3564. I just did a keyboard test in pretty dim lighting (1/6 sec, f/5.6, ISO 1600), and the results are pretty much identical to scaling 200% in PhotoShop right down to the ISO noise. With no apparent loss of IQ using the digital Teleconverter, it seems to be a reasonable way to compose your enlargements live versus cropping in post process.
Thanks for testing this and the explanation. I will be using this more often with my 12-40 zoom when out and about with one body as I mostly use JPEG output.

Will come in handy as well for video too. Have set it to the lens function button.
 

sgreszcz

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IF you shoot video this is one very cool tool. It along with IBIS makes this a great video camera as long as you don't pan fast. If Oly would up grade their codec or when the have 4K, I would find the EP5 the perfect camera. I'd sell my other stuff and go 2 EP6/7/8 whatever and be happy.
In my testing, I found that the digital teleconverter looks quite bad and creates much more digital artefacts and "rough" looking video than with the DTC off. So for video there is no free lunch...
 

D7k1

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In my testing, I found that the digital teleconverter looks quite bad and creates much more digital artefacts and "rough" looking video than with the DTC off. So for video there is no free lunch...
Using the camera on a tripod and using the 40-150mm, I found it very good. Were you using the 1080 HQ? From what I under stand in the Movie DC it does nothing more that use the center of the image which is full resolution. The codec does not like fast movement in either the camera or the subject.
 

Replytoken

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Using the camera on a tripod and using the 40-150mm, I found it very good. Were you using the 1080 HQ? From what I under stand in the Movie DC it does nothing more that use the center of the image which is full resolution. The codec does not like fast movement in either the camera or the subject.
I thought it was Panasonic's Extended Tele mode that only used the center of the image unsampled, and that Oly did resample in DC. Incorrect assumption?

--Ken
 
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