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06-15-2009, 09:18 PM   #1
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They Said It Couldn't Be Done! (Taming The Beast)

This is part one, part two has my galleries from the Red Bull Air Races in Windsor with both the Sigma 100-300 F4 and the Rokinon 800mm F8.

Well those who know me know i demand top quality from my lenses, i will only buy a consumer grade lens if it has something that appeals to me. Well i went and bought myself a Rokinon 800mm F8 mirror lens. It also can be found under the Samyang and Vivitar Series I names. Typically a mirror lens has so many faults and people can find heaps to complain about with regards to them.

I figured that at $324ca. after shipping and duties and taxes i could afford to buy this lens as a toy to play around with and that if i didn't like it i could just put it up on ebay at a small loss or use it as a paper weight or for experimentation purposes..

I read many reviews and these are the sorts of things being said...

You must use a tripod to get any decent result
- With built in stabilization i could get a sharp result on a still object at 800mm (1200mm) and 1/160th sec hand held

The bokeh has a bad donut appearance
- True but so far it only shows up in 10% of my photos

You just can't get a sharp result
- Well its no consumer grade 70-300 with regards to resolving micro details but edge sharpness isn't that bad

There is no contrast
- This is true and its due to the design of the lens, you'll see a diagram in this review that refers to why the contrast is lower then the average lens, if you shoot a photo of someones head and try to find individual hairs in a group of hair they're all smudged together, whereas a regular lens would have them more clearly and sharply defined.

Mirror Lenses - how good? Tamron 500/8 SP vs Canon 500/4.5L

The DOF is very shallow and you can't stop down
- This is true, 800mm F8 at 3.5m is 4.5mm, but for head shots at 20m the DOF is 18cm

There are a few that complain about CA
- Well i say my 100-300 F4 has negligible amounts of CA but the 800mm F8.0 has next to none except for a few times where the subject was slightly out of focus against an overcast sky but like i said the $324 mirror lens beats my $1500 Sigma 100-300 F4

You need to use a high ISO in daylight to get any decent shutter speed
- This is true, you'll see in this post that i used ISOs 1600-3200 in overcast conditions

Focus is twitchy and tricky
- It can be but focus trap is very helpful

F8.0 is very dark in the viewfinder making it hard to manually focus
- Not really, sure its darker then an F4 lens but its still pretty good

The F-stop may be F8 but the T-stop is F11
- This is apparently true as the center mirror blocks a good stop of light from entering the mirror lens

You can only use these lenses for still photography in bright light, certainly not for sports or any other action
- This is not true... with focus trap i got some unlikely results at the Red Bull Air Races, in fact i got a rather high number of in focus shots of planes going at high speeds and doing fancy maneuvers and sharp turns, you'll see the galleries later in this post

This is a lens for those who are willing to be patient taking a picture of a still subject
- Well planes racing around a course certainly are still and patients will only make you miss photos.

Mirror lenses tend to get a bad rap and have bad stigmas linked to them but the fact is at 30 times cheaper then typical 800mm F5.6 lenses and 6 times lighter and many times smaller you can still get very decent results if you know what you're doing.

now go to part II

06-15-2009, 09:20 PM   #2
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Part II... Red Bull Air Races (2 Galleries)

Well I decided to see if i could tame the beast, As you read in part one a mirror lens is unusable for any kind of action or sports.

I mounted the lens on the camera using foil to short the data pin and very importantly the recessed pin on the mount in order to access Tv and Auto ISO, the camera thought the lens was an 800mm F1.2 LOL... regardless of the fact that it thought it could change the aperture the metering was maintained. the ISO would compensate for the aperture not changing even though the camera thought otherwise. I left the shutter speed at 1/1600th sec and SR on however i might have done better with SR off. with it being overcast it required ISO1600-3200 to maintain 1/1600th sec at F8.0. i set the camera to AF-S and burst mode. i held my finder on the shutter and followed the planes all the time adjusting the focus to get a sharp result... 800mm on a full frame camera is 3 degrees field of view, on a crop frame its 2 degrees. it is not easy to locate the plane with a 2 degree FOV. however i did ok! I also set the camera to bright mode, ramped the sharpness up to max and the contrast up to max to counter the soft low contrast effect of the mirror lens (yes i shot JPEG).

Here is the first qualifying round of the air races shot with the Sigma 100-300 F4 and sometimes i had the Sigma 1.4x teleconverter on...
Red Bull Air Races ~ Windsor Ontario Canada ~ Qualifying Round 1 ~ Sigma APO 100-300mm F4 EX DG and Sigma 1.4x EX DG (at times)

Here is the second qualifying round od the air races shot with the Rokinon 800mm F8.0
Red Bull Air Races ~ Windsor Ontario Canada ~ Qualifying Round ~ Rokinon 800mm F8.0 Mirror Lens ~ ISO1600-3200

Yes the ISO is higher with the mirror lens so the noise is higher, the WB may be more off and there is no micro contrast detail but you get much closer and its obviously still capable of shooting action.

Unlike some other brands we have the benefit of in body SR, however optical SR would be nice when working with 800mm (1200mm). Pentax also is the only other brand that focus traps, sure others focus confirm but then you have to hit the trigger at the right time. My K20D and a bit of foil gave me access to auto ISO and shutter priority, i'm not sure how many other brands give you these options with a manual lens.

Yes it is obvious that the Sigma 100-300 F4 gives a sharper result and has more fine details, and may likely match or better the mirror lens if re-sized up. the mirror lens can't quite match the 100-300 F4 when re-sized down but again its 5 times cheaper and no slouch for that price.

Now a few last things, for those Canadians out there I have named this lens my Tim Hortons lens as it looks like a coffee can (can of coffee grounds) and it gives me donuts LOL. for those unfamiliar with Tim Hortons its a very popular coffee shop in Canada. So we have Pancake lenses, muffin or cupcake lenses (ltds and stubby lenses like the 35mm F2 and 50mm F1.4) and now we have a donut/coffee can lenses LOL

I have just received in the mail 2 lens hoods, each 7.3cm long and 105mm threads, one should be enough but 2 still doesn't vignette. i hope to used them to minimize veiling glare however i haven't had a chance to fully test the differences

Final thoughts, Don't go out and buy this lens due to my results, study the subject and be very aware of what you're buying and the limitations. its not a $10000 lens! don't expect quality like that. they don't come with aperture control, the design doesn't permit an aperture. if you have money to waste and you want a new toy to play with then by all means. if you feel you can tame the beast and you want a cheap super tele lens and you have the money to do it then go for it. however if this is out of your league and you aren't willing to push the limits of photography then don't even consider it. If you have $10000 to put on a lens buy an 800mm F5.6 instead.
I hope you liked the photos and this review
06-15-2009, 09:29 PM   #3
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Thanks for the indepth review Mike! Love the pics. Its very easy to lose focus with the mirror because the DOF is very thin and a small rotation goes a long way. (That or I need to learn focus trap, haha I still do things the old school way)

I have the Rokinon 500/6.3. I bought a 95mm lens hood (more like a tube) and its helped the flare issue a bit. I should pull it out more often.
06-15-2009, 09:44 PM   #4
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QuoteOriginally posted by FotoPete Quote
Thanks for the indepth review Mike! Love the pics. Its very easy to lose focus with the mirror because the DOF is very thin and a small rotation goes a long way. (That or I need to learn focus trap, haha I still do things the old school way)

I have the Rokinon 500/6.3. I bought a 95mm lens hood (more like a tube) and its helped the flare issue a bit. I should pull it out more often.
Wow a local with the 500mm F6.3... i'm in Brampton and i'd like to try the 500mm, any chance we could get together? the reason i bought the 800 is that i can achieve 510mm F6.8 with the 100-300 F4 and 1.7x AFA and that is close enough to 500mm F6.3 that i decided to go for something more exotic

06-15-2009, 09:57 PM   #5
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Hey Mike, yea sure! Anytime! HAha those 800mm pics look fantastic...almost too good!
06-15-2009, 10:08 PM   #6
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When this came out, I wondered whether it used the Vivitar Solid Cat design or was different. Do you know?
06-15-2009, 10:10 PM   #7
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It sounds like there were at least 3 people from the forums out at the race; SouthShoreRob has posted some photos from his Sigma 135-400mm and I was there with a Vivitar Series One 70-210mm. For most of the race action I would have been better off with something in the 300 to 400 mm range but it was still a fun day.
06-15-2009, 10:22 PM   #8
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QuoteOriginally posted by Just1MoreDave Quote
When this came out, I wondered whether it used the Vivitar Solid Cat design or was different. Do you know?
I just read up on those... neat stuff but this definitely has air between the front lens and rear mirror so its not a solid cat design

06-15-2009, 10:24 PM   #9
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QuoteOriginally posted by Steinback Quote
It sounds like there were at least 3 people from the forums out at the race; SouthShoreRob has posted some photos from his Sigma 135-400mm and I was there with a Vivitar Series One 70-210mm. For most of the race action I would have been better off with something in the 300 to 400 mm range but it was still a fun day.
great stuff... which side were you on and whereabouts? I was onthe Canadian Side and the east most side of Dieppe Park
06-15-2009, 11:00 PM   #10
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Excellent review there Mike from Canada. I think you may have broken the ice for posting of pics from the big mirror lenses. I have been using my Rok 800mm for 2 months now and found as long as there is strong light, especially low angle morning/afternoon, I can get shots with the color and contrast that rival traditional lenses. Guess I should start posting some 800mm shots too.
06-16-2009, 06:14 AM   #11
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QuoteOriginally posted by imtheguy Quote
Excellent review there Mike from Canada. I think you may have broken the ice for posting of pics from the big mirror lenses. I have been using my Rok 800mm for 2 months now and found as long as there is strong light, especially low angle morning/afternoon, I can get shots with the color and contrast that rival traditional lenses. Guess I should start posting some 800mm shots too.
PM me when you do post some so i don't miss it, i'd like to see your results
06-16-2009, 06:38 AM   #12
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Great work there Mike.
You've done remarkably well with the mirror lens - very sharp relatively...
Awesome stuff.
06-16-2009, 10:15 AM   #13
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Great shots as always! But curse you for making my wallet itch...
06-16-2009, 02:16 PM   #14
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QuoteOriginally posted by Ash Quote
Great work there Mike.
You've done remarkably well with the mirror lens - very sharp relatively...
Awesome stuff.
thanks Ash... more to come, i've decided that its a keeper lens
06-16-2009, 02:17 PM   #15
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QuoteOriginally posted by Marc Sabatella Quote
Great shots as always! But curse you for making my wallet itch...
be careful you know what you're getting into if you dare to buy... i'll provide full unedited samples of any of the shots from 800mm F8.0 just so you know what the quality is straight from the camera
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