p.2 #1 · SP/XP 14mm /2.4 Rokinon testing and images
No time for any real testing as I was losing light on an overcast day. Nonetheless, this lens does show some promise. Rokinon 14/2.4 @ 2.4. 1:1 crop of the upper left corner included.. I notice that this lens is very easy to over sharpen too.
p.2 #2 · SP/XP 14mm /2.4 Rokinon testing and images
AGeoJO wrote:
Mike, thank you for evaluating the lens. It seems to be a more than decent performer with respect to coma to me. As such, the lens appears to be a contender for an excellent astro lens . Do you think the other corners perform similarly to the top left corner that you looked at though? Thanks again!
Joshua, I didn't have a chance to take a full set, just one with good center focus and stars up in the left corner. I'll find a darker time and do a full set on Sunday if I can brave the cold.
p.2 #3 · SP/XP 14mm /2.4 Rokinon testing and images
mcbroomf wrote:
My lens arrived by Fedex at midday (UPS are usually late in the day) so I was able to do some preliminary tests. As a simple 1st check I slapped an adapter on it, focused in the center on the roof and trees of my back neighbour at high mag, then moved the focus point to one of the corners. The corner was terrible! I checked another corner and got the same thing. I had put on an MB IV adapter and it was focusing on infinity well before the stop, so I switched over to an MC-11 which only went a fraction of a turn to the stop past infinity. Completely different lens! Well we've seen this before but not sure I have on my own lens. All tests below with the Sigma.
This lens is definitely better than the 14mm AF Rokinon lenses I tried. I think it's also better than an older MF Rokinon that I sold but perhaps not better than a very good one. It seems pretty well centered but it takes ~F4 to really shine in the corners. It will be clear tonight so I'll point it at some stars.
The crops below were taken @WO, 2.8, 4 and 5.6. Tripod, no IBIS, remote. The WO shows up as F2.2 in the camera and LR and I got the same with both the MB and Sigma adapters. I was also going to try it on a Viltriox but it would not go on and I wasn't about to force it.
1/2 way through creating the jpgs I realized I left my LR import preset on, so it's got CA reduction and my pretty aggressive capture sharpening and other tweaks. I'll upload some default files when I have some more time.
p.2 #5 · SP/XP 14mm /2.4 Rokinon testing and images
Nothing special here but some shots all at f/11. The lens is certainly sharp. I would say that this lens sunstar performance is rather weak. Nothing like the Voigtlander Helliar 15/4.5 III.
p.2 #6 · SP/XP 14mm /2.4 Rokinon testing and images
rji2goleez wrote:
Nothing special here but some shots all at f/11. The lens is certainly sharp. I would say that this lens sunstar performance is rather weak. Nothing like the Voigtlander Helliar 15/4.5 III.
The lens looks promising, Bob. Thanks for your evaluation. The light source (sun) of the sunstar in your image is too big probably. If you try a street lantern or similar at night the rendition of the sunstar should be better than that.
p.2 #8 · SP/XP 14mm /2.4 Rokinon testing and images
AGeoJO wrote:
The lens looks promising, Bob. Thanks for your evaluation. The light source (sun) of the sunstar in your image is too big probably. If you try a street lantern or similar at night the rendition of the sunstar should be better than that.
I did a quick try last night on my garage door lights and it wasn't good but I don't consider that a good test just yet. Stay tuned . . .
p.2 #9 · SP/XP 14mm /2.4 Rokinon testing and images
i had the samyang 14mm 2,8 for several years, and it was tack sharp - but the sunstar was not that great. This one seems a bit better. wonder what it would look like at f/22?
p.2 #10 · SP/XP 14mm /2.4 Rokinon testing and images
One more quick corner test. This looks pretty good . . . I would say even awesome. Shot wide open. I wish it weren't so cloudy as I am really curious about astro now.
p.2 #14 · SP/XP 14mm /2.4 Rokinon testing and images
rji2goleez wrote:
One more quick corner test. This looks pretty good . . . I would say even awesome. Shot wide open. I wish it weren't so cloudy as I am really curious about astro now.
I don't know about any one else, but IMHO that's pretty incredible for wide open, especially for an extreme wide angle like this.
p.2 #16 · SP/XP 14mm /2.4 Rokinon testing and images
Bespoked wrote:
Makes sense! I thought it was strange, I thought to myself, why would he add ugly flares in post? lol
Thanks for the samples, I really appreciate it. I've been seeing them come in for a few months and none of them are what I want to see, but we're getting closer.
If you can, I'd love to see architecture to assess distortion characteristics which from your samples looks very well controlled!
I've seen some barrel distortion when shooting straight onto a wall or similar subject. Of course there is no profile on this lens in LRCC just yet. Let me see if I still have that image.
Crops from; center, top left, top right and bottom right (re-oriented to vertical so the crop comes from the top right again). Each image was taken; WO, F2.8 and F4.0 (crops are in that order). Tripod, IBIS off, 640 ISO, 10 secs, 2 sec timer (could not get my remote working and too cold to fiddle around)
I reset LR to it's defaults (so no high levels of capture sharpening or CA correction) but then adjusted highlights, white, shadows blacks and noise reduction to show the stars clearly as possible given that it was a full moon.
p.2 #20 · SP/XP 14mm /2.4 Rokinon testing and images
I've ordered some SS foil which will be here tomorrow and plan to shim one of my Metabones adapters. I'll take a before and after to show the smearing. I'm hoping to get it spot on for infinity to compare to the Sigma which is very close.
I think this lens is a keeper although I'd like to retest everything (diagonal infinity and stars as I was working quickly and think I may have focused a bit too far). I can see a slight amount of coma, but it's no worse that the very slight star motion also visible for a 10 sec exposure so I don't think I'm worried about it, even on a decent sized print (I typically evaluate at ~50% for a large print)
. Do you think the other corners perform similarly to the top left corner that you looked at though? Thanks again!
