Opinions about buying a lens?

I have a Nikon D5100, and I've been saving up for a 50mm f/1.8 for a while now, and financial situations aren't fabulous at the moment, and it'll take me much longer than it's worth to save up for the 50mm f/1.8G that has the ability to autofocus on my entry level DSLR. I can currently afford the 50mm f/1.8D, but it can't autofocus on my camera, and the material is a little cheaper. I think I'm going to go ahead and buy it, but not without some opinions.

Are there any major disadvantages to buying this lens that overpower however many years it would take to save up for the 1.8G? Is this lens a good choice, and is having only manual focus a huge deal?
>>> Opinions about buying a lens?

Why did Canon and Nikon introduce new lens mounts for their mirrorless cameras?

The E-mount and Micro Four Thirds were already open mounts they could have taken advantage of, or gone the Pentax route and introduced a mirrorless based on their existing lens mount. The MFT mount has so many lenses because several manufacturers got together on it. Nikon and Canon could have joined up with Sony on the E-mount to do something similar, or got on the MFT band wagon.

What's more is that both of their mirrorless offerings are crippled and seem to make very little sense.It's like they were afraid to make them good and compete with their own DSLRs.
>>> Why did Canon and Nikon introduce new lens mounts for their mirrorless cameras?

Why has Nikon lost market share over the past few years?

Why has Nikon lost market share over the past few years?
>>> Why has Nikon lost market share over the past few years?

Does Vivitar 100-300mm lens fits on Nikon D3100?

I have a Nikon D3100 and I wanna know if the Vivitar 100-300mm lens can fit on my Nikon D3100.It's an older lens so I have no idea it can fit or not. Please Let me know! Here are some information about the lens: Vivitar 100-300mm close focus to zoom. 1:5. K-mount. HELP PLEASE!
>>> Does Vivitar 100-300mm lens fits on Nikon D3100?

Nikon D3000 flash problem?

Ive had my Nikon for about 2 years and all of a sudden every time i try to take a picture with the flash on, the flash pops up but makes a clicking noise every time i try to take picture and the flash wont go off.Is there any non- dangerous way i can fix it myself without having to go to a camera place
>>> Nikon D3000 flash problem?

Is the rokinon 28mm f2.8 lens compatible with Nikon d200?

Hi.thinking about getting this lens, but could not find out if it was compatible with the mount on my nikon d200 anywhere on the internet, any info appreciated.
thanks in advance.
>>> Is the rokinon 28mm f2.8 lens compatible with Nikon d200?

How will my bullet be effected at long range?

I recently got a 22-250 for christmas (savage axis only $330 with scope). I'm only 15 but I have been studying all the scope adjustments and things need to take long distance shots. I have been using the nikon spot on program. I set a target at 450 and fired 3 shots. 2 hit. 1 was about 2.5 inches from my 1" bullseye and one about 5.5 inches.So today with a 15 mph crosswind i set my target at what ended up being 693 yards, adjusted my scope how i thought i should and without thinking i would hit anything fired 3 shots. Well, all 3 hit. They were 4.5 inches, 5.5, and 9 inches from the bullseye. I want to try to take a 930 yard shot, cause that's the farthest shot i can take before i run out of room, but my bullet drops below the sound barrier at about 800 yards (hornady v-max 55 gr.at about 3500 fps). How will the sound barrier effect the bullet. I have never taken a shot over 350 yards until i got this gun so i have no clue what i need to do to make these shots besides the elevation and windage adjustments that i have been correctly making. I understand all the MOA adjustments and things like that but what else would i need to take into account? I know my 22-250 isn't ballistically ideal for an almost 1000 yard shot but could it even make the shot? Thanks for any help.
Added (1). The rifle is sighted in at 100 yards with me shooting under 1 inch groups. I am just making my adjustments based on a 100 yard sight in and making them correctly.So i'm thinking if i keep all my math consistent as the range increases and plug in the new data as i should, i should be able to make the 930 yard shot just the same as the 2 others.
>>> How will my bullet be effected at long range?

Do you need a separate meter to shoot with a dslr back in a 4x5 camera?

I am going digital and will be shooting with a nikon dslr back with a horseman using a convertor. Will i need to use my light meter still or can i leave it behind?
>>> Do you need a separate meter to shoot with a dslr back in a 4x5 camera?

In '5 stop VR reduction compensation' what does 5 stop means?

This is in relation to buying Nikon lenses and heard this term in AF-S NIKKOR
70-200mm f/4G ED VR lens review.

Already bought a 50mm 1.8D Prime. Thank you all for the past inputs :)
>>> In '5 stop VR reduction compensation' what does 5 stop means?

What gives better hd video quality, a DSLR or a camcorder?

I want to buy a panasonic 3mos which is around the £1000 mark but would a Nikon DSLR at half the price be just as good quality wise
>>> What gives better hd video quality, a DSLR or a camcorder?