Cressi Giotto vs Aqualung i300

[JoRoPiTo]

Hello everyone.

I'm new here, this is my very first post.
I would like to know if someone has tested both Giotto and i300 to share some thoughts.

I have those in my list to buy but I can´t decide which one (the price I found is almost the same)

Currently I'm AOW going into technical+rescue and will try DM and Instructor level next year.
I'm not going to do thousands of dives in a year but I want to get the computer.

Best regards

 

[stuartv]

Currently I'm AOW going into technical+rescue and will try DM and Instructor level next year.
I'm not going to do thousands of dives in a year but I want to get the computer.

Best regards

The best choice (in my mind) for what you want to do is a Shearwater Perdix or Perdix AI. Any particular reason you are not considering that as an option?

When you go into tech, either computer you are looking at will likely become a backup, at best. If it doesn't have Gauge mode, it won't even be that useful.

If the Perdix AI had been around when I started tech training, I would have saved myself a decent amount of money by just buying that right up front.

 

[CrumhornDiver]

The best choice (in my mind) for what you want to do is a Shearwater Perdix or Perdix AI. Any particular reason you are not considering that as an option?

When you go into tech, either computer you are looking at will likely become a backup, at best. If it doesn't have Gauge mode, it won't even be that useful.

If the Perdix AI had been around when I started tech training, I would have saved myself a decent amount of money by just buying that right up front.

Also, check the computer marketplace here. A Perdix will hold it's value well. If you decide it's more computer than you need or give up diving before getting to tech training, you will likely not lose more than you would on one of the other models. If you end up doing tech training, you will not need to upgrade. If you decide a Perdix is too much right now, I agree with @stuartv that getting a computer that has a gauge mode would be helpful so it can be used as a backup later should you so choose.

 

[JoRoPiTo]

Both models support EANx 21% to 50% and Gauge. I don't want t spend too much.

The only big differences I found are automatic altitude, salt/fresh water selection and freedive on i300.

 

[dmaziuk]

Both models support EANx 21% to 50% and Gauge. I don't want t spend too much.

The only big differences I found are automatic altitude, salt/fresh water selection and freedive on i300.

Are you sure about that? I was confused by the giotto manual myself for a while, but it actually is a 2-gas computer supporting pure O2.

 

[uncfnp]

Yes, the Giotto will do up to 99% O2.

The other significant difference is in the algorithm. The Cressi runs RGBM and the i300 runs a version of PZ+. Its the subject of much debate and numerous threads but as a general rule the i300 is considered more liberal then the Giotto. In other words it will give you a bit more bottom time on repetitive dives.

Neither DC will carry you very far into the tech world. Both are fine for beginner to advaned recreational diving.

 

[dmaziuk]

The only reason I can think of for pure O2 w/ 2 gases is to support deco on pure O2. Whereas AL's manual states up front "no-stop dives only". Which to me makes a huge difference.

 

[stuartv]

The only reason I can think of for pure O2 w/ 2 gases is to support deco on pure O2. Whereas AL's manual states up front "no-stop dives only". Which to me makes a huge difference.

There are people (at least one on this very board) who are unusually susceptible to DCS. A person like that might choose to take the Advanced Nitrox class (without Deco Procedures) and then carry and use a cylinder of O2 during their safety stop, even though they did not exceed their NDL.

Also, if one wanted to increase their NDL on a repetitive dive, one could use O2 (and a computer that will recognize it) during the safety stop of the previous NDL dive, simply to clear more N2 out of your system. I.e. the equivalent of a having a longer surface interval.

Not very many will go to the trouble. But, I guess a few will/do.

 

[dmaziuk]

I suppose... still, having gas switching and corresp. calc. switching during the dive is I think way bigger difference than algorithm and

The only big differences I found are automatic altitude, salt/fresh water selection and freedive on i300.

 

[stuartv]

The only big differences I found are automatic altitude, salt/fresh water selection

For the record, salt/fresh selection is kind of a marketing thing and that's it. Deco calculations are done based on the pressure sensor data, so they will be correct regardless of what type of water you're in and what type the computer THINKS you're in.

The ONLY thing that will be affected by the salt/fresh selection is the depth that is displayed. If the selection is "wrong", then the depth that is displayed to you and recorded in the log will be off by a small amount from what your actual depth is. But, again, that does not matter to the deco calculations. Deco (i.e. NDL times) are based on the actual ambient pressure, which is what it is and doesn't matter whether you're a little shallower and in salt water or a little deeper and in fresh water. It's the ambient pressure which determines your inspired gas pressure which determines how quickly nitrogen is being absorbed by your tissues.