[shoulder]

lo solucione cuando grabo :

Código Delphi [-]
var
ftblob : tblobtype;
begin
      zquery1.Active;
      zquery1.close;
      zquery1.SQL.Clear;
      zquery1.sql.add ('insert into xxx (..., ..., digital)');
      zquery1.sql.add ('values..,... :digital)');
      zquery1.Params.ParamByName('....').Value := 'Documento';
      zquery1.Params.ParamByName('...').Value := 'kk';
      zquery1.Params.ParamByName('digital').LoadFromFile('c:\foto.jpg',  
      ftblob);
      zquery1.Active;
      zquery1.ExecSQL;

cuando traigo los datos

Código Delphi [-]
var
ftblob : Tblobfield;
jpg : TJpegImage ;
begin
 
      zquery1.Active;
      zquery1.close;
      zquery1.SQL.Clear;
      zquery1.sql.add ('select digital from ....');
      zquery1.sql.add ('where codigo = 1');
      zquery1.Active := True;
      zquery1.Open ;
      ftblob := zQuery1.FieldByName('digital') as TBlobField;

      jpg:= TJpegImage.Create;
      jpg.Assign(ftblob);
      image1.Picture.Graphic:=jpg;