Simple answer: 35mm and 50mm (or Sigma 30 and EF50F1.4) > William.so you are recommending(to be safe and have coverage) to go with the EF35 f/2.8 and what.? < Hence in that scenario even the 30mm is a very tight lens to shoot a conservatively small family of 4, in a modest sized room. The point is: you are struggling to get any variance in formal arrangements, and it is totally impossible, to have Dad standing in any image, and shoot landscape, with those FoV figures. You choose to shoot down the 15ft, but you can`t move the book cabinet which takes up 18inches, so effectively with you are one end and the family neatly and comfortably arranges at the other, you have a working subject distance of about 10 ft.Īt 10 ft a 30mm lens on a 40D will give a FoV(v) = 5 ft 6 inches, and a FoV(h) = 10 ft. Getting back to the lounge room, it has the usual chairs etc, which you move around, but the dimensions are a cosy 15ft x 12 ft.
#SIGMA VS GC PRO BOX FULL#
The lounge room is the biggest / most suitable room and the family asks for a more traditional style of Full Length Portrait image, for the Grandparent`s Photo Collections, (irrespective of your photographic style, that request is money in the bank for you). I am not answering for Tim, but, what I was getting at is: pretend we are inside a lounge room with a family of 4 and the dog. Lens on your camera if you like the 50mm focal length. This certainly doesn't mean it is a "bad lens" - I have one and I like it a lot. (It is a great landscape lens at small apertures,Įspecially of full frame.) However, at f/1.4 its sharpness diminishes noticeably and it loses contrast. Stopped down a bit - say f/2 or so and smaller. The 50mm f/1.4 is a fine optical performer but with a caveat or two. Unless you _really_ need that lens, the f/1.8 version should work quite well. One eye might be in focus and the other OOF if you aren't careful. You don't actually want to shoot at the widest aperture - at 85mm and f/1.2 you'll have an extremely While the 85mm f/1.2 is reportedly a fine lens, it is also a very costly and large lens. More typical choices would be in the 50mm or 85mm range on a crop body (though some In eukaryotes transcription is terminated by two elements: a poly(A) signal and a downstream terminator sequence ( 7).If you are getting a portrait lens, the important features are (more or less in order of importance):įocal length, maximum aperture, IQ, price, etc.įew people would choose a 30mm focal length for a portrait lens - not impossible, but an usualĬhoice. Termination in prokaryotes is done by either rho-dependent or rho-independent mechanisms. Eukaryotes contain mRNAs that are monocystronic. mRNAs in prokaryotes tend to contain many different genes on a single mRNA meaning they are polycystronic. These events do not occur in prokaryotes. RNAs from eukaryotes undergo post-transcriptional modifications including: capping, polyadenylation, and splicing. Another main difference between the two is that transcription and translation occurs simultaneously in prokaryotes and in eukaryotes the RNA is first transcribed in the nucleus and then translated in the cytoplasm. There is no such structure seen in prokaryotes. Eukaryotes form and initiation complex with the various transcription factors that dissociate after initiation is completed. Eukaryotes have three types of RNA polymerases, I, II, and III, and prokaryotes only have one type. Eukaryotes contain many different promoter elements: TATA box, initiator elements, downstream core promoter element, CAAT box, and the GC box to name a few. The pore in which RNA exits and where NTPs comes into the polymerase are conserved as well ( 4).ĭifferences: Prokaryotes only contain three different promoter elements: -10, -35 promoters, and upstream elements. Beta and Rpb2 as well as beta’ and Rpb1 show sequence homology. The Rpb3 and Rpb11 show the same fold as the alpha subunit in bacterial polymerase. Rpb3 and Rpb11 also form a subcomplex with Rpb2. Alpha 2 binds beta to form a subcomplex that then binds beta’ that form the core enzyme. Similarity in sequence has been shown between alpha, Rpb3, and Rpb11. Comparisons between bacterial and RNA polymerase II have been performed.