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Andrew Reid

SLR Magic Rangefinder footage - kiss goodbye to focus breathing / Kowa anamorphic goes single focus

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As far as the minimum focus of 1m I think its just a case of "no free lunch".  Its would take a seriously entitled person to expect life to be perfect for them all the time.  If the markings on the rangefinder really are accurate at every setting on every lens I frankly find it amazing that is even possible at all.

I'm no mathematician but I was wondering if the focus scales logarithmically:  So, for example, if you calibrated your lens to so it had a 0.5m minimum focus distance at the 1m setting, would the 50m marking then give accurate focus for 25m?   Perhaps this is wishful thinking, but if this or some other useful correlation could be established then maybe the focus markings could still be useful with a closer minimum focus.

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Yes you do. You need to focus the taking lens back to the other end. (and if the taking lens doesn't have a hard infinity stop, it'll take time calibrating both to infinity - you set the RG to infinity, go out the window to find a horizon or a star at night, adjust focus on the lens until infinity is achieved and glue at that somehow, any inaccuracy in doing this renders the marks on the RG unusable/inaccurate). 

You can also be more nerdy and focus the RG to the MFD of 5 feet and measure and put subject 5 feet away from the sensor plane and adjust the taking lens until it's in-focus and glue it. Either way you're calibrating the RG with the Lens and after doing so, 3'6 is the MFD. 

This is an issue with the version with distance marks but I think with the blank cheaper version since you don't care about calibrating the numbers, you can just focus closer than 3'6 with the taking lens and bring it back to the other at any time (you don't ''need'' to be accurate)

@dafreaking I confirm, it fixes fly by wire lenses. Just set it to infinity and focus with the cine smooth 270° one of the RG. 

For the first time I am getting SOO accurate focus for land scapes with the 10-18mm. I specially like Cine focus rings with wide angle lenses when depth of field is deep, since focus shifts are not so visible and it's so hard to nail with a photo focus ring, with 85mm 1.8 I can focus just fine with a photo lens as the changes are so apparent on the screen. It's a godsent for wide angles. 

This is brilliant. 

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Guest Ebrahim Saadawi

I was shooting with the RG today on my Nikon D7100 coupled with the 24-120mm F4 out on the streets, real world experience with it for the first time so I noticed something, 

The focus ring on the Rangefinder has inconsistent resistence throughout the focal range. Being loose-est at MFD and stiff-est at infinity. 

I took the rangefinder off and took it back in the lab to see if it was something I am just imagining but yes even when not attached to a lens and pointed 90° to the gravity center, the focus ring is loose from 3'6 to about 5'9 percisely where it becomes considerably stiffer, has more resistence, and it even becomes slighty loose-er/smoother again staring from about 8' to infinity, but still markedly more stiff than the MFD to 5'9 range.

Overall whilst shooting it required marked muscle force variation from my part to keep it consistently focusing while following a subject. 

I then tried and handed it to one of my employees, a physician with no knowledge whatsoever of what a lens is, and I asked him to turn the focus ring and see if there's inconsisteny, he gave me the exact same numbers. 

I expect this is a intended design for some reason I am simply uninformed about?

or the fact that simply the prototype model have been abused therefore gathering dust/grease before I recieved it?

Or perhaps a design flaw caused by the changing in the focus ring position while focusing, being farthest from the mechanical body at MFD range. 

I would love to hear other testers thoughts on this (Andrew Reid, Zac, Sebastian, anyone) and whether this is something you see in your samples. 

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yes, the resistance is inconsistent, but only slightly so, on mine. but like the softness and the chromatic aberrations it introduces, these are the minor sacrifices you make for something that is half (and potentially one-quarter) the price of The Rectilux -- the optics of which are far superior and don't introduce any additional image degradation beyond what the taking lens and scope would have on their own. In fact, I was able to easily disassemble my Rectilux and grease it to a resistance level of my liking. I would have no hesitation recommending the Rangefinder to someone who is looking for a balance of price and "good enough". For that reason, they will likely sell a gazilion of them. But if price is not an issue and you want the best, get the Rectilux.

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@Ebraham - Mine is fine.  If yours is stiff then send it back to SLR Magic.  This is a pre-production model and it will have problems.  I had problems with my prototype 1.33x Anamorphot, sent it back and got a newer version no charge.  So contact Andrew and let him know the problems.  They always had excellent customer service.

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Guest Ebrahim Saadawi

Thank you Zak and Nahua for the quick reply. Zak please report this to Andrew too, I did, lets see if there's more complaints from the testers. 

The resolution and CA minor changes are not bothering me even one bit, actually loving them in 4K, and flaring is gorgeous. I accept those. It's such an innovative product.

 But I am not sure customers will accept an inconsistent resistant cinema focus ring. SLR Magic smaller lenses focus rings are perfect, this needs to be fixed before production if it's not yet. Must be fixed. It's a cine grade focus ring, must be consistent and linear. It's a small inconsistency but enough to annoy me today while shooting, the good part is it smoothly gets stiffer, not abruptly at a point, so I was able to memorize and be able to adjust my palm muscle force according to the ring resistence to get smooth pulls. A buying customer will not be as tolerant as I am as just a prototype tester though. 

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Bringing this thread back from the dead.

I'm testing the Rangefinder this week with a Takumar 50mm and Singer 16D. One thing I noticed is that when comparing the RF on and off, it really distorts the background vertically, through the RF. It's not subtle either. When the rangefinder is off the image is pleasant and looks like typical anamorphic distortion, but when the RF is on it's like I stretched everything vertically. Is that just a characteristic of the RF?

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On 9/23/2016 at 6:42 PM, AaronChicago said:

Bringing this thread back from the dead.

I'm testing the Rangefinder this week with a Takumar 50mm and Singer 16D. One thing I noticed is that when comparing the RF on and off, it really distorts the background vertically, through the RF. It's not subtle either. When the rangefinder is off the image is pleasant and looks like typical anamorphic distortion, but when the RF is on it's like I stretched everything vertically. Is that just a characteristic of the RF?

can you share images, I'm not sure I can imagine how much disstortion you're talking about :s

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12 hours ago, Justin Bacle said:

can you share images, I'm not sure I can imagine how much disstortion you're talking about :s

Justin, I will upload a couple later today. I posted this question in the anamorphic section and got some good info. Any type of diopter, including variable, will add some stretch vertically.

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2 minutes ago, AaronChicago said:

Justin, I will upload a couple later today. I posted this question in the anamorphic section and got some good info. Any type of diopter, including variable, will add some stretch vertically.

Do you prefer the look without the Rangefinder?

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2 hours ago, AaronChicago said:

I do. It seems more natural but with the normal anamorphic properties (barrel distortion, oval bokeh, flares).

Are you sure the Rectilux would give you the same distortion. Sounds like the Rangefinder is gonna drive you nuts, because you'll always know how much better your footage will look without it.

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RF isn't worth it in my opinion, if you're spending decent cash to get a half-decent scope you might as well pay the bit extra and also get a core DNA. Buy once, cry once.

SLR magic also have horrible looking coatings, I hope they fix these issues someday in the future as it's good for the market to have competition, right now though there's none, Rectilux is miles ahead.

I mean what's the point getting one of these systems if every time you review the footage you wish you were shooting with it off...

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55 minutes ago, tweak said:

RF isn't worth it in my opinion, if you're spending decent cash to get a half-decent scope you might as well pay the bit extra and also get a core DNA. Buy once, cry once.

SLR magic also have horrible looking coatings, I hope they fix these issues someday in the future as it's good for the market to have competition, right now though there's none, Rectilux is miles ahead.

I mean what's the point getting one of these systems if every time you review the footage you wish you were shooting with it off...

Well if I knew the Rectilux was much better in this area I'd get it in an instant. I can still return the RF. 

I really wish I could shoot without it but I'm not great at all with dual focussing. If it's a stationary shot I'll definitely go bare.

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9 hours ago, AaronChicago said:

Well if I knew the Rectilux was much better in this area I'd get it in an instant. I can still return the RF. 

I really wish I could shoot without it but I'm not great at all with dual focussing. If it's a stationary shot I'll definitely go bare.

Yeah I'd return it, if you can afford the CDNA there's no reason why you wouldn't get that. CDNA introduces almost zero extra artefacts to your image where as RF slaps it's ugly blue flares all over everything. Personally I can't stand the look of those flares, they aren't even the nice type of blue.

I still use a lot of dual focus setups but I agree it's not that handy especially in run and gun or situations with not much time to prepare the shot, it's easy to think you're in focus when you're actually slightly off. I guess that all just becomes better with experience and understanding your scopes well. Still if I were doing paid shoots I would invest in a CDNA no questions.

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As the optical principle of RF, coreDNA and vintage single focus solutions (iscorama) is the same (variable diopter), I would be surprised if there are large differences in things like defocus quality etc. But that's an educated guess, could be wrong.

I just received my 72mm RF, tested it briefly and yes, the blue blobs are easily summoned ;-) I do intend to try a cheap circular hood on the RF to see if it helps. At any rate, the thing is built like a tank and finally being able to more easily use my anamorphics will be a relief.

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