spyder0109 wrote:
Andy01 wrote:
spyder0109 wrote:
Landscapeforfun wrote:
Be careful of the 16-35 f/2.8 III. While it is fantastically sharp it is really only f/2.8 in the center. It has over twice as much vingetting in the corners compared to the 16-35 f4. The 16-35 f/4 will actually give you a brighter image in about 30% of the frame. This is important for Astro since your stars are likely to be most prominent in those areas.
Option 4 would be the tamron 15-30 f/2.8. It’s very sharp, has IS, and is priced similarly to the 16-35 f/4. It is an amazing deal but doesn’t take screw on filters and is quite heavy.
Thanks for the suggestion.
I have more or less made up my mind to first buy Irix (not rokinon) 15mm f/2.4 for astro requirements. And in next 2-3 months or so, if required I will go for Canon L-series 16-35 F/4 IS.
I have heard some good reviews from Tamron 15-30 but yes it being very heavy was a deal-breaker for me. (And it being tamron as well - i am kinda biased to L-series lenses - would rather get it)
With the Irix 15mm, make sure it is somewhere reliable that will accept returns. I have just received my second copy, and so far, not happy with it either. Nice features, but it seems quite soft for distant subjects - daytime only so far.
In theory it seems like a nice lens, and online pics are nice and sharp, and I thought it would have to be better than a Samyang / Rokinon 14mm f2.8 (which has a particularly poor reputation for QC) but it seems that Irix is not much better.
Colin
Aha
i am based out of Singapore and here I don’t have official dealers for neither Rokinon nor Irix. And was planning to buy from an official dealer in Hong Kong, which I’m visiting from April 28.
One of my biggest reasons to switch to Irix was Rokinon’s well documented quality issues between units.
Now, I would buy early during my trip and use the lens, so that if required, I can change it before leaving Hong Kong itself.
Thanks
OK update time. I may have been premature in my judgement of the Irix 15mm and given you a bum steer. It helps to get some real data and do more extensive testing.
I did more testing today, with somewhat different results. I went to a local camera shop and tried the following lenses in a non-scientific test where I fitted the lenses to my own 6D ii and stood outside the door and took photos at all apertures of the scene across a busy 6 lane road with shops, street signs etc across the road. It was mostly sunny weather so shutter speeds were generally 1/1250th or higher at larger apertures. All shot in RAW.
I have to admit that based on the few snaps I had taken earlier this week in my street I had almost written off my Irix 15mm Firefly, and had already primed the seller for a return.
Irix 15mm Firefly (mine)
Irix 15mm Blackstone
Samyang 14mm f2.8 ED (old one). Nikon mount so I borrowed their D750.
Samyang 14mm f2.8 AF
Samyang 14mm f2.4 XP Premium
Sigma 14 f1.8 Art
And I also shot the same scene using my M5 + 11-22mm EFM at 11mm, which is 17.6mm FF equivalent.
The results for sharpness only (looking at parts of the scene at 200% of the unprocessed RAW images on my 27" Dell Ultrasharp monitor). From best to worst for a centre-biased view but also considering edges. I looked at f2.8 and f4 mostly as all lenses had f4, and all but my 11-22mm had f2.8.
Irix 15mm Firefly - BIG suprise !
Sigma 14mm f1.8 - surprised it wasn't better in outright sharpness. Good contrast, colours & minimal vignetting etc. A nice lens, although it is a big heavy beast. The first series of pics I took (using AF) were all out of focus, so I switched it off and on again, and it worked OK after that. May be a Sigma - 6D ii issue ?
Samyang 14mm f2.4 XP - actually a nice lens. Significantly better than the basic old 14mm f2.8 ED, although double the price.
Canon 11-22mm f4 - obviously taken with the M5, not 6D ii
Irix 15mm Blackstone - it didn't seem as crisp as mine
Samyang 14mm AF - average - at first the AF didn't work, so I switched it off and on again to get it to work.
Samyang 14mm f2.8 ED - this is the older (original ?) Samyang/Rokinon. I had to use the Nikon D750 with my card in it, and since I don't know Nikon it almost certainly wasn't setup to my liking. The Nikon version of the lens does operate with the cameras aperture control (when set to f22 on the lens) whereas the EF mount version needs manual on-lens control. It was awful - not in the slightest bit sharp - dramatically worse than the next worse in my opinion. I really wouldn't recommend this based on what I saw, but I have to say that I was comparing it using a different and unfamiliar camera although that shouldn't affect sharpness.
The vignetting on the Irix is probably the worst wide open, with the Sigma the best, and the corner sharpness on the Sigma was probably the best. The price order is interesting too, from cheapest (in Australian $), Canon 11-22mm ($423), Samyang f2.8 ED ($529), Irix 15mm Firefly ($740), Irix 15mm Blackstone ($989), Samyang 14mm f2.8 AF ($1079), and then a decent jump to Samyang 14mm f2.4 XP (at $1248 about 70% more than the Firefly), and then a large jump to Sigma 14mm f1.8 (at $1798 the Sigma is almost 2.5x the price of the Firefly).
So, I am now in a much better frame of mind regarding the Irix 15mm Firefly and I am quite optimistic that it will perform well, and am looking forward to taking some real world photos with it. I will not be returning it.
There really wasn't much between the Firefly, Samyang 14mm XP, Sigma 14mm and Blackstone in sharpness, and it took some pixel peeping at 200% to pick them. I think that if money was no object, I would buy (in order of preference) Sigma 14mm f1.8, Samyang 14mm XP, Irix Blackstone, and then Irix Firefly, but when considering value for money, I do think that the Firefly probably has the others beat, although there is going to be a bit more PP to correct vignetting. The infinity notch/click (and focus locking ring) of the Irix lenses is a very useful feature that none of the others have which would make it useful for astro.
I would still suggest a quick brick wall test to check for decentering for the Irix 15mm (and probably any Samyang) because my first copy of the Firefly was quite obviously defective, but I am now much happier to recommend the Irix 15mm.
Colin
